Glossary of Diamond and Jewelry Terms, Terminology and Definitions

LAST UPDATE ON: October 30th, 2024

Below are definitions and links to pages, articles, or other content covering Diamond and Jewelry topics in depth.

000

What is 000?

: A triple zero, triple 0 or 000 diamond refers to one graded by the American Gem Society, with the top grade of 0 (zero) in Performance or Proportions, Symmetry and Polish. It originally referred to a diamond with top grades in color, clarity and cut, but that interpretation is rarely used.; Learn More …

4 CS

What is 4Cs?

: The Diamond 4Cs are Carat weight, Color, Clarity and Cut.; Learn More …

60/60 DIAMONDS

What is 60/60 Diamond?

: 60/60 diamonds are a subset of round brilliant diamonds with table measurement near 60%, combined with depth near 60%. 60/60 diamonds generally produce white light return over fire.; Learn More …

ABRASION

What is Abrasion?

: A diamond abrasion is an area of unpolished surface usually seen at a facet junction as a result of wear. In appearance it resembles a white scratch. It is often caused by contact with other diamonds. In gemstones, it is caused by contact with materials harder than that gemstone.; Learn More …

ACTUAL DIAMOND IMAGE

What is Actual Diamond Image?

: An actual diamond image is a photograph of a specific diamond. It is not a stock/sample image or computer generated image. Sellers frequently post images and video for diamonds they are selling. An actual diamond photo (or video) is more useful for making determinations than a sample image (which tells you nothing) or computer generated image (which is subject to mechanical error).; Learn More …

AGS 0

What is AGS 0?

: Also known as AGS Ideal, AGS 0 (zero) is the top grade in the AGS system. It is widely used in reference to cut quality, but color and clarity are also graded on a 0-10 scale, in addition to receiving standard international nomenclature.; Learn More …

AGS GRADING SCALE

What is AGS grading scale?

: AGS grading is done on a 0-10 scale with 0 being ideal, or “zero deductions”. In addition to cut quality, color and clarity are graded on the numerical scale but receive equivalent grades according to the international scale developed by the GIA.; Learn More …

AGSL

What is AGSL?

: AGSL stands for American Gem Society Laboratories, a diamond grading laboratory based in Las Vegas, Nevada, specialized in grading diamond cut quality and light performance.; Learn More …

AIR HOLES

What is Air Holes?

: Air holes are tiny holes drilled in a setting under small gemstones to permit light to enter from beneath. They also assist in the ease of cleaning those small diamonds.; Learn More …

ANNIVERSARY RING

What is Anniversary Ring?

: An anniversary ring is typically a band given as an anniversary gift or three stone ring, representing your past, present and future.; Learn More …

ANTIQUE OR VINTAGE

What is Antique Ring?

: Antique or vintage rings are designs influenced by past style trends. These designs may include such details as beading, milgrain, art deco influences, engraving, scallop or scroll work and pavé set diamonds.; Learn More …

APPRAISAL

What is Appraisal?

: An appraisal is a valuation of property. Appraisals are typically used for insurance and taxation purposes or to determine a possible selling price. Independent jewelry appraisals are those done by an expert who is uninvolved in the selling of diamonds or jewelry. In-store appraisals may be offered by sellers of the item being appraised. In-store appraisals which reflect the selling price are often suitable for insurance purposes but are not considered objective.; Learn More …

APPROXIMATE SIZE & SHAPE

What is Approximate Size?

: Sellers may show a sample image which is representative of the diamond being sold. When “approximate size” matches the shape, measurement, and length to width ratio of the actual diamond it can be used to convey the approximate size and shape of the diamond.; Learn More …

ARTISANAL MINING

What is Artisanal Mining?

: Artisinal miners typically work independently of mining companies, mining minerals using their own resources, usually by hand.; Learn More …

ASET

What is ASET?

: The Angular Spectrum Evaluation Tool (ASET) is a device on which the foundation of the AGS light performance cut grading system is built. ASETs come in different sized, from simple hand-held reflectors to professional desktop models. They device are used to assess brightness, leakage and contrast in loose diamonds and diamonds set in jewelry.; Learn More …

ASSCHER

What is Asscher Cut Diamond?

: The Asscher cut diamond is a variation of the classic emerald cut, first produced in 1902 by the Asscher Brothers of Holland. Asscher cuts are square in shape and have distinct cut corners, which add to their geometric appeal, making the diamond appear almost octagonal. They first peaked in popularity in the 1920’s. Around 2002, one hundred years after the first asscher cut diamond was created, the shape began to make a comeback, spurred on by cut modifications that gave the shape more brilliance than traditional asscher cut diamonds.; Learn More …

AZIMUTH

What is Azimuth?

: Azimuth is a measurement of the direction in which a facet is pointing.; Learn More …

BAGUETTE SHAPE

What is Baguette Diamond?

: A baguette is a rectangular-shaped diamond with rows of step-like facets. If the baguette’s two long sides taper inward, it is called a Tapered baguette.; Learn More …

BANK WIRE

What is Bank Wire?

: A bank wire is an immediate transfer of funds from one bank account to another. A bank wire differs from an Automated Clearing House (ACH) transfer because it is immediate and irreversible, protecting the recipient from cancelation.; Learn More …

BAR SET

What is Bar Setting?

: A bar is a thin piece of metal which holds a stone in place, similar to a channel setting. When a series of stones are set next to each other using the bar technique, you will see a narrow bar between each stone.; Learn More …

BARION CUT

What is Barion Cut?

: The Barion cut is named after a combination of Basil Watermeyer and his wife’s first names, Basil and Marion. It has a traditional step-cut crown and a modified brilliant-cut pavilion. A square barion cut diamond has 61 facets, excluding the culet.; Learn More …

BEADING OR MILGRAIN

What is Beading?

: Beading or milgrain is representative of little ‘beads’ of metal used to accent the edge of a setting or its design features like the halo, bezel or as a pattern to add additional adornment to the style.; Learn More …

BEARDED GIRDLE

What is Bearded Girdle?

: A bearded girdle suffers from a series of tiny feathers at the girdle, extending into the diamond, which typically resulted from the cutting process. The bearding can sometimes be removed, if not too dramatic, with slight re-polishing, and if the weight allows.; Learn More …

BEZEL FACET

What is Bezel Facet?

: On a round brilliant diamond, the eight large kite-shaped facets on the crown are referred to as bezel facets, also kite facets and crown main facets.; Learn More …

BEZEL SET

What is Bezel Setting?

: A bezel setting is a prongless style that uses a rim of metal to hold the stone, completely surrounding it, leaving only the upper portion, above the girdle, showing. Bezels can be plain metal or accented with diamonds or gems and often have smooth edges, but can be scalloped or molded into any shape to accommodate the stone.; Learn More …

BLEMISH

What is Blemish?

: Diamond blemishes are external clarity characteristics which may include abrasions, nicks, extra facets, polish marks, naturals, and scratches. Many are not visible to the naked or untrained eye.; Learn More …

BLOCKING

What is Blocking?

: Blocking is a preliminary step in diamond cutting. For round diamonds, it involves placing the first 8 facets on both crown and the pavilion, establishing the primary angles and proportions.; Learn More …

BORT

What is Bort?

: Bort refers to industrial grade diamonds, which are not suitable for jewelry, often used by apprentice diamond cutters for practice.; Learn More …

BOW TIE

What is Bow Tie?

: A bow tie refers to a dark area running across the center of the diamond, frequently seen in enlongated fancy shapes, such as marquise, oval, pear, and radiant cut diamonds.; Learn More …

BRANDED DIAMONDS

What is Branded Diamond?

: A branded diamond is one which belongs to a curated collection. Branded diamonds may be offered by a single seller, or sold through many authorized retailers. Brands can be proprietary cuts featuring unique faceting arrangements, or standard cuts like round brilliant, princess, etc., curated by the seller as part of that store’s ‘signature’ brand.; Learn More …

BRILLIANCE

What is Brilliance?

: Brilliance refers to the brightness of a diamond, created by the combination of all light reflected to the viewer from the surface and within the polished diamond.; Learn More …

BRILLIANT

What is Brilliant Cut?

: The Brilliant cutting style uses triangular or kite-shaped facets. The round brilliant and princess cut are examples of this style which promotes scintillation and contrast, which is quite different than step cuts which feature horizontally shaped facets.; Learn More …

BRILLIANT 10 DIAMOND

What is Brilliant 10 Diamond?

: The Brilliant 10 diamond has 10 main crown and pavilion facets, rather than the traditional 8 main crown and pavilion facets.; Learn More …

BRILLIANTEERING

What is Brillianteering?

: When cutting a round brilliant diamond, brillianteering occurs after the table and 16 main facets are established. It is the process of polishing the final forty facets on the diamond including the upper and lower girdle and star facets.; Learn More …

BRUISE

What is Bruise?

: A Bruise is a tiny area of impact accompanied by very small, root-link feathers which typically occurs at a facet junction.; Learn More …

BURN MARK

What is Burn Mark?

: A burn mark, also called a polish mark, is surface clouding caused by excessive heat during polishing.; Learn More …

BURNISH SET / FLUSH SET

What is Burnish Setting?

: Burnish setting, also known as the flush set style, occurs when the stone is inserted into a tapered hole that has been drilled into the band, and a burnishing tool is then used to push the metal all around the stone, so that the stone is flush with the surface of the band.; Learn More …

CARAT

What is Carat?

: Carat Weight is one of the Diamond 4Cs. A carat is the standard unit of measurement referring to the weight of a diamond. One carat is equivalent to 200 milligrams, or one-fifth of a gram. The term carat originates from the seed of the Carob tree. In ancient times, before scales and units of mass were invented, diamond traders compared the weight of a diamond to the seeds of the carob tree. Each carob seed has a uniform weight, equal to approximately 200 milligrams.; Learn More …

CARBON

What is Carbon?

: The average diamond is approximately 99.95 % crystallized carbon. The other 0.05 percent can include one or more trace elements, which can influence its color appearance or crystal shape.; Learn More …

CARBON SPOTS

What is Carbon Spots?

: Some people refer to black inclusions within a diamond as Carbon Spots. This is a laymen’s term, not official, since such inclusions may actually be a wide variety of opaque characteritics which are not necessarily composed of carbon.; Learn More …

CATHEDRAL SETTING

What is Cathedral Setting?

: A cathedral setting is a style of ring where either side of the band arches up and reaches towards the center stone.; Learn More …

CAVITY

What is Cavity?

: A cavity is a tiny opening that breaks a diamond’s surface, frequently where a crystal inclusion was dislodged and fell out.; Learn More …

CERTIFICATE

What is Certificate?

: The term certificate is used to refer to a diamond’s grading report. It’s not an accurate term, since most gemological laboratories do not “certify” the details, they only report them as a matter of assessed opinion.; Learn More …

CERTIFICATION

What is Certification?

: The term certificate is often used to refer to a diamond’s grading report. It’s not an accurate term, since most gemological laboratories do not “certify” the details. The grading report includes an assessment of the diamond’s 4Cs: Carat weight, measurements in millimeters and judgments involving color, clarity, and human craftsmanship. Laboratory grown diamonds will be identified as such on any top tier laboratory’s grading report.; Learn More …

CERTIFIED GEMOLOGIST (AGS)

What is Certified Gemologist?

: An American Gem Society (AGS) Certified Gemologist (CG) has first completed the GIA graduate gemology program (GIA GG) followed by the AGS certified gamologist program and is employed by an AGS member store.; Learn More …

CHANNEL SETTING

What is Channel Setting?

: Channel setting is a style of setting where the stones line up next to each other and are supported between two bars or strips of metal, referred to as channels. This setting is used most frequently for wedding and anniversary bands.; Learn More …

CHEVRONS

What is Chevron?

: Chevrons are the “V” shaped sets of facets on the pavilion of a princess cut diamond.; Learn More …

CHIP

What is Chip?

: A chip is a shallow opening on the diamond’s surface which can result from any hard impact along a cleavage plane, most frequently seen at the girdle, facet junction, or culet.; Learn More …

CLARITY

What is Clarity?

: Clarity is one of the Diamond 4Cs: As diamonds crystallized, chemicals and elements became trapped within their crystal lattices. Clarity evaluates a gemstone’s relative freedom from such internal characteristics, classified as inclusions, and from surface characteristics, classified as blemishes.; Learn More …

CLARITY

What is Clarity Grading?

: Clarity grading involves an assessment of a diamond’s inclusions and blemishes by a gemologist using a special scope and a 10x magnification. The collective visibility at 10x, along with the location, number, color, size and nature of a diamon0d’s inclusions determine the diamond’s clarity grade.; Learn More …

CLARITY CHARACTERISTICS

What is Clarity Characteristic?

: Clarity characteristics include internal characteristics, classified as inclusions, and from surface characteristics, classified as blemishes.; Learn More …

CLAWS

What is Claw Prong?

: Claw prongs are a style choice where each of the prongs holding the stone are shaped into a shaper point or claw. Typical settings feature 4 or 6 claws or prongs.; Learn More …

CLEAVAGE

What is Cleavage?

: Cleavages are the natural areas of a diamond or gemstone where the atomic bonds are weaker. When a stone needs to be ‘split,’ a gemstone cutter will cleave it along its cleavage planes/cleavage lines.; Learn More …

CLOUD

What is Cloud?

: A cloud is an inclusion term which refers to areas of tightly grouped pinpoints. Depending on size and density of the grouping of pinpoints it can be entirely invisible, or can cause issues with light transmission which make a diamond appear hazy, milky or “sleepy.” The clarity grade is important to consider. Clouds in diamonds graded VS and above are generally benign. Clouds in diamonds graded SI and below may interfere with optical qualities. A diamond with the clarity grade “based on clouds not shown” should be avoided in the VS grades and below.; Learn More …

COATING

What is Coating?

: A thin layer of material over another material used to change its nature. For example, a layer of synthetic diamond over a non-diamond material designed to defeat certain types of diamond testers, or a layer of harder material over a softer material to improve its hardness.; Learn More …

COLOR

What is Color?

: Color is one of the Diamond 4Cs. Color refers to the amount of body color a diamond has, most commonly yellow or brown, but also in other colors, categorized as fancy colored diamonds. The color of a diamond is an important characteristic because it is noticeable to the untrained eye. It has the second most influence on a diamond’s color after carat weight.; Learn More …

COLOR

What is Color Grading?

: Gemological laboratories perform color grading in the normal D-Z range with the diamond upside down, examined from the side, comparing the diamond against known master sets of diamonds. Fancy Colored Diamonds are assessed in the face-up position, viewed normally.; Learn More …

COLOR ORIGIN

What is Color Origin?

: Color origin is the cause of a colored diamond’s hue, including natural, enhanced, high temperature, and high pressure treated.; Learn More …

CONFLICT DIAMONDS

What is Conflict Diamond?

: Conflict diamonds is a term developed in the 1990s, referring to diamonds in impoverished West African nations associated with human rights violations and/or used to fuel conflict between militant groups and legally established governments. The United Nations’ Kimberley Process was instituted in 2003, uniting legitimate governments of countries where diamonds are mined, cut and traded against conflict diamonds, reducing the issue by more than 99%.; Learn More …

CONTRAST

What is Contrast?

: Contrast is the differential brightness between adjoining facets which contributes to the perception of brilliance, fire and scintillation.; Learn More …

CROWN

What is Crown?

: The crown of a diamond includes everything above its girdle.; Learn More …

CROWN ANGLE

What is Crown Angle?

: The crown angle refers to the number of degrees between the plane of the table and the bezel facets. The crown angle, in combination with the table size and pavilion angle, will determine how much light is reflected into the pavilion at an angle that will allow it to be reflected back up through the crown, where the observer can perceive it.; Learn More …

CROWN HEIGHT PERCENTAGE

What is Crown Height?

: The crown height measures how high above the girdle the crown reaches, and is expressed as a percentage of the average girdle diameter.; Learn More …

CRYSTAL

What is Crystal?

: A crystal is an inclusion, typically a mineral deposit found inside a diamond, either alone or in groups. Crystals may be transparent or opaque.; Learn More …

CUBIC ZIRCONIA (CZ)

What is Cubic Zirconia?

: The most popular lab grown imitation diamond (simulant) on the market today.; Learn More …

CULET

What is Culet?

: A culet, if present, is a small facet polished onto the bottom of a diamond or gemstone which replaces the sharp point that would normally be present at the tip of the pavilion. Most diamonds do not have a culet at all. When present it can range from very small to an extremely large culet, which is basically an extended, flat surface.; Learn More …

CUSHION CUT

What is Cushion Cut?

: A cushion cut diamond, which evolved from the old mine cut style, combines a square cut with rounded corners, much like a pillow. Including the old mine cut, this shape has existed for over two centuries, and for the first century of its existence was the most popular diamond shape.; Learn More …

CUT

What is Cut?

: Cut is one of the Diamond 4Cs. A diamond’s cut refers to its overall geometry, including the proportions (measurements and angles) which determine how light will behave within the stone.; Learn More …

CUTTING STYLE

What is Cutting Style?

: Cutting styles refer to the type and combination of faceting used on a diamond. Brilliant cuts employ kite shaped facets. Step cuts employ rectangular facets. Mixed cuts employ both styles.; Learn More …

CUBIC ZIRCONIA (CZ)

What is Cubic Zirconia?

: The most popular lab grown imitation diamond (simulant) on the market today.; Learn More …

DAHLIA CUT

What is Dahlia Cut?

: A Dahlia Cut diamond has an oval shape with flat ends. This shape was invented in the 1990s for De Beers by Antwerp cutter Gabi Tolkowsky.; Learn More …

DEEP CUT

What is Deep Cut?

: A deep diamond, also known as a steep-deep diamond, is one where wide cutting angles was used to increase the diamond’s final weight, maximizing yield. Those wide angles cause some of the light entering the diamond to leak out of the bottom, instead of reflecting and returning to the viewer’s eyes. When removed from bright lights, steep deep diamonds quickly go dark and look physically smaller than they should.; Learn More …

DEPTH

What is Depth?

: Depth refers to a diamond’s height, measured in millimeters from its point or culet to its table, often expressed as a percentage of the average width, or girdle diameter.; Learn More …

DEPTH PERCENTAGE

What is Depth Percentage?

: A diamond’s depth percentage is the heigh of the diamond, expressed as a percentage of its average width.; Learn More …

DIAMCALC

What is DiamCalc?

: DiamCalc is a diamond design and analytics program designed by Octonus Software to study diamond light performance.; Learn More …

DIAMOND

What is Diamond?

: A diamond is the hardest known natural substance. It is crystallized carbon. Diamonds are mined in their rough form and then cut and polished for aesthetic appeal.; Learn More …

DIAMOND ANATOMY

What is Diamond Anatomy?

: Diamond Anatomy refers to the groups of flat polished surfaces called facets, arranged in specific patterns on the Crown, Girdle, and Pavilion; Learn More …

DIAMOND CERTIFICATE

What is Diamond Certificate?

: A diamond certificate (or grading report) is issued by an independent gemological laboratory, following a secure, standardized diamond grading process. It’s an assessment of the diamond’s 4Cs.; Learn More …

DIAMOND DETECTOR

What is Diamond Detector?

: A diamond detector or diamond tester is an instrument designed to indicate whether a stone is a diamond or some other substance.; Learn More …

DIAMOND DIMENSIONS

What is Diamond Dimensions?

: A diamond’s dimensions are its length, width, and depth (in that order), expressed in millimeters. For round and square diamonds, the length and width should be close to identical.; Learn More …

DIAMOND GRADING REPORTS

What is Diamond Grading Report?

: A diamond grading report (sometimes called a certificate) is issued by an independent gemological laboratory, following a secure, standardized diamond grading process. It’s an assessment of the diamond’s 4Cs.; Learn More …

DIAMOND HYBRID®

What is Diamond Hybrid?

: The Diamond Hybrid is created by placing a perfectly cut crystal core or substrate into a chamber of intense heat and pressure and infusing lab-created diamond crystals, or bonding them at a molecular level, into the outer layers of the crystal core.; Learn More …

DIAMOND PLOT

What is Diamond Plot?

: A diamond plot, when it appears on a report, maps a diamond’s internal and external clarity characteristics.; Learn More …

DIAMOND TREATMENTS

What is Diamond Treatment?

: Diamond treatments refer to a variety of techniques used to artificially improve the natural color or clarity of a diamond.; Learn More …

DIAMONDSURE

What is Diamondsure?

: Diamondsure is a detection device developed by DeBeers to identify natural diamonds and refer suspected synthetic or treated diamonds for further testing.; Learn More …

DISPERSION

What is Dispersion?

: Dispersion is the prismatic separation of white light into its individual color components as a result of refraction within a diamond. When the resulting sparkles are perceived as color they are called fire.; Learn More …

DOSSIER

What is Dossier?

: A dossier is a shorter version of a grading document for diamonds which does not include a clarity plot. The diamond is laser inscribed with the dossier report number for identification purposes.; Learn More …

DOUBLE PRONG

What is Double Prong?

: A double prong uses two prongs of the same size and shape created side-by-side to hold the stone in place.; Learn More …

DURABILITY

What is Durability?

: The durability of a diamond or gemstone refers to a combination of its hardness, stability, and toughness. It is ultimately the best way to determine how a stone will respond to intense wear.; Learn More …

EGL

What is EGL?

: The EGL (European Gemological Laboratories) was a collection of loosely affiliated grading labs operating in different cities around the world. Largely known for “overgrading” diamonds, most of the operations have ceased to be.; Learn More …

EIGHT CUT / SINGLE CUT

What is Eight Cut?

: Also called “single cut”, an eight cut diamond has only eight pavilion mains and eight crown mains, for a total of 17 facets. Eight cut is usually restricted to melee (very small diamonds).; Learn More …

EMERALD CUT

What is Emerald Cut?

: An emerald cut is a square or rectangular cut diamond with diagonal corners. Most emerald cut diamonds have between two and four rows of facets that lie parallel to the girdle.; Learn More …

EMERALDS

What is Emerald?

: Emeralds are their own unique type of gemstone, member of the Beryl family, not to be confused with emerald cut diamonds.; Learn More …

ENGAGEMENT RING

What is Engagement Ring?

: An Engagement Ring signifies commitment to engagement and eventual marriage. Typically worn on the fourth finger of the left hand.; Learn More …

ENGRAVING

What is Engraving?

: Engraving is a form of etching that adds design details to the outer band of a ring or is used to inscribe a personal message inside of a band. It can be done by hand or with a laser,; Learn More …

ETCHED CHANNEL

What is Etched Channel?

: An etched channel is a rare clarity characteristic, typically a void caused by a dissolution event sometime during a diamond’s formation.; Learn More …

ETERNITY

What is Eternity Ring?

: An eternity ring or eternity band describes a ring with side stones extending all the way around the band, without any plain metal showing. Half eternity and 3/4 eternity styles also exist.; Learn More …

EX-EX-EX / TRIPLE EX / 3X / 3EX

What is EX-EX-EX?

: A Triple EX, or 3EX diamond is one with an excellent cut grade, along with excellent polish and excellent symmetry.; Learn More …

EXCELLENT CUT

What is Excellent Cut?

: The excellent cut grade is the highest offered by some grading laboratories. Others have a higher grade, called Ideal cut.; Learn More …

EXTRA FACET

What is Extra Facet?

: An extra facet is a clarity characteristic. It’ describes a facet that is not a part of the shape’s standard faceting pattern. It is usually added by the cutter due to a limitation or flaw in the original rough stone.; Learn More …

EYE CLEAN

What is Eye-Clean?

: The PriceScope definition of Eye-Clean is no inclusions visible to the unaided eye when viewed from the face up position in daylight equivalent or fluorescent lighting between 6-12 inches from the eye using 20/20 vision.; Learn More …

FACET

What is Facet?

: A facet is a small flat surface that is polished on a diamond or gemstone.; Learn More …

FACETED DIAMOND

What is Faceted Diamond?

: A faceted diamond is one that has been converted from a rough crystal into a polished stone with all of its facets.; Learn More …

FACETED GIRDLE

What is Faceted Girdle?

: A faceted girdle on a round brilliant typically consists of 32 polished facets. Unfaceted girdles also exist, but tend to be present on older diamonds.; Learn More …

FACETWARE

What is Facetware?

: Facetware is a prediction page from GIA that permits input of basic proportions to see the GIA cut grade result.; Learn More …

FACEUP APPEARANCE

What is Faceup appearance?

: Faceup appearance is the first impression the diamond makes when viewed through the table with the naked eye.; Learn More …

FAIR CUT

What is Fair Cut?

: Fair cut is the fourth or fifth category on the cut grading scale: (Ideal), Excellent, Very Good, Good, Fair, Poor.; Learn More …

FANCY

What is Fancy?

: Fancy cut diamonds are shapes other than the common round brilliant, including princess, oval, pear, marquise, heart, cushion and other examples.; Learn More …

FANCY COLOR

What is Fancy Color?

: Fancy Colored diamonds are those with body color other than yellow or brown, as well as yellow and brown diamonds with more saturation than the common range (D-Z). Fancy color diamonds have their own grading system.; Learn More …

FANCY CUT

What is Fancy Cut?

: Fancy cut diamonds are shapes other than the common round brilliant, including princess, oval, pear, marquise, heart, cushion and other examples.; Learn More …

FANCY SHAPE

What is Fancy Shape?

: Fancy cut diamonds are shapes other than the common round brilliant, including princess, oval, pear, marquise, heart, cushion and other examples.; Learn More …

FEATHER

What is Feather?

: A feather is a common clarity feature caused by a slight separation in the crystal lattice of the diamond. It’s the trade term for a break in a gemstone, which is often white and feathery in appearance.; Learn More …

FILLING

What is Filling?

: A diamond filling is a substance placed into a break in a diamond in order to improve its appearance. Fillings are not permanent and may become altered or lost when exposed to heat or ultrasonic cleaning.; Learn More …

FINGERPRINT

What is Fingerprint?

: A fingerprint is a trade term for a unique identifying characteristic in a diamond; Learn More …

FINISH

What is Finish?

: The finish of a diamond refers to surface craftsmanship involving its polish and facet symmetry.; Learn More …

FIRE / DISPERSION

What is Fire?

: Fire is colored flashes detected by your eyes as a result of the prismatic separation of white light into its individual color components due to refraction within a diamond.; Learn More …

FISH EYE

What is Fish Eye?

: A fisheye is a negative effect which occurs when the girdle is seen reflected in the table of a diamond at a small angle of tilt, usually the result of shallow depth and large table facet.; Learn More …

FL (FLAWLESS) GRADE

What is Flawless?

: A gemstone with no characteristics visible at 10 power magnification, is considered flawless (FL), and a gemstone with surface blemishes but no inclusions can be graded internally flawless (IF).; Learn More …

FLAT-TOP SETTING

What is Flat Top Setting?

: A flat top setting has a band that is one continuous piece which gets thicker at the top.; Learn More …

FLAW

What is Flaw?

: A flaw is a nickname for a diamond clarity characteristic, also called inclusions or imperfections.; Learn More …

FLUORESCENCE

What is Fluorescence?

: About 30% of diamonds have some amount of fluorescence, caused by chemicals in the earth where it formed. Fluorescence can be excited by ultraviolet light or x-rays, and re-emit visible light. In most cases fluorescence is blue, but colors such as yellow, white, orange and red are possible.; Learn More …

FLUSH FIT

What is Flush Fit?

: A flush fit setting sees the stone inserted into a tapered hole that has been drilled into the band, and a burnishing tool is then used to push metal around the stone, so that the stone is flush with the surface of the band.; Learn More …

FOUR CS

What is Four Cs

: The Diamond 4Cs are Carat weight, Color, Clarity and Cut.; Learn More …

FRACTURE

What is Fracture?

: A fracture is a crack or break on a diamond’s surface.; Learn More …

FRACTURE FILLING

What is Fracture Filling?

: Fracture filling is a treatment which involves putting a substance with the same refractive index as the gemstone in a break or fracture. It is not permanent, as substances may become altered or fall out when exposed to heat or ultrasonics.; Learn More …

GEMSTONE

What is Gemstone?

: A gemstone may be a rock, a mineral, or any organic or inorganic material that is cut and polished for jewelry.; Learn More …

GGG

What is GGG?

: GGG stands for Gadolinium Gallium Garnet, which followed YAG and preceded CZ as an early artificially produced diamond simulant.; Learn More …

GIA

What is GIA?

: Established in 1931 by Robert Shipley, the GIA (Gemological Institute of America) is widely considered the world’s foremost authority on diamonds, colored stones, and pearls.; Learn More …

GIA CERTIFICATE

What is GIA Certificate?

: A GIA certificate is used to refer to a GIA diamond grading report. It’s not an accurate term, since most gemological laboratories do not “certify” the details, they only report them as a matter of assessed opinion.the two types of certification offered by GIA.; Learn More …

GIA DOSSIER

What is GIA Dossier?

: The GIA Dossier is an abbreviated form of the GIA Grading Report, often used for smaller diamonds. It is available for a lower fee and has a 4Cs assessment but no clarity plot, so laser inscribing the GIA report number is a required and included service.; Learn More …

GIA EXCELLENT

What is GIA Excellent?

: GIA Excellent is the top grade in the GIA cut grade system.; Learn More …

GIA GRADING REPORT

What is GIA Grading Report?

: A GIA Grading Report is one that has been issued by the GIA, providing their judgment on the characteristics and quality of a gemstone.; Learn More …

GIRDLE

What is Girdle?

: A diamond’s girdle sits above the pavilion and beneath the crown. It is typically faceted or polished but may remain rough on some diamonds.; Learn More …

GIRDLE REFLECTION

What is Girdle Reflection?

: Girdle reflection is a reflection of the diamond’s girdle within the stone, typically seen when viewed from the side. Girdle reflections are frequently mistaken for a flaw or crack within the stone.; Learn More …

GIRDLE THICKNESS

What is Girdle Thickness?

: Girdle thickness is a measurement describing the percentage of the diamond’s average girdle diameter, accompanied by a description of extremely thin, thin, medium, slightly thick, thick or extremely thick.; Learn More …

GLETZ

What is Gletz?

: Gletz is an industry term for a visible clarity characteristic within a gemstone.; Learn More …

GOLD

What is Gold?

: Gold is a precious metal represented by the chemical element Au. Pure gold is yellow in color and soft, which is why it is usually alloyed with other metals, such as silver, copper, platinum or palladium, to increase its strength or alter its color.; Learn More …

GOOD CUT

What is Good Cut?

: Good cut is the third or fourth category on the cut grading scale: (Ideal), Excellent, Very Good, Good, Fair, Poor.; Learn More …

GRADING REPORT

What is Grading Report?

: A Grading Report is one that has been issued by a grading laboratory, providing their judgment on the characteristics and quality of a gemstone.; Learn More …

GRADUATE GEMOLOGIST (GIA)

What is Graduate Gemologist?

: The graduate gemologist (GG) title is a credential issued to a student who has successfully completed the entire set of courses offered by a gemological institute and passed the final exam.; Learn More …

GRAIN

What is Grain?

: A grain is a trade term for 0.25 carats. A 1.00 carat diamond may be referred to as a 4-grain diamond, or 4-grainer.; Learn More …

GRAIN CENTER

What is Grain Center?

: A grain center is a small, concentrated area of crystal distortion which can be white or dark, and might have a thread-like or pinpoint-like appearance.; Learn More …

GRAINING

What is Graining?

: Graining may appear within a diamond as lines showing the crystal structure’s growth pattern. Graining can be external or internal.; Learn More …

GREEN

What is Green Diamond?

: Green is a very rare natural fancy color when it occurs in diamonds, caused by radiation in the earth where the diamond formed.; Learn More …

GROWTH OR GRAIN LINES

What is Growth Lines?

: Graining or growth lines may appear within a diamond as lines showing the crystal structure’s growth pattern. Graining can be external or internal.; Learn More …

GYPSY SETTING

What is Gypsy Setting?

: The gypsy setting is predominantly used for men’s jewelry. The band is one continuous piece that gets thicker at the top. The stone is typically inserted in the middle of the dome shaped top.; Learn More …

HALF BEZEL

What is Half-Bezel

: A half-bezel setting is also referred to as semi-bezel. This is a style of setting that uses a rim of metal to hold the stone, surrounding two sides while leaving two sides open, exposing the diamond’s girdle.; Learn More …

HALO

What is Halo Setting?

: The halo setting adds a “halo” of small accent stones surrounding the center stone. The main advantage of this style is more sparkle directly around the center stone, making it appear larger.; Learn More …

HARDNESS

What is Hardness?

: Hardness is a mineral’s resistance to scratching on a smooth surface, typically measured on the Mohs scale of hardness ranging from 1-10. Diamond measures 10 on the Mohs scale and is the hardest of all gemstones.; Learn More …

HCA

What is HCA?

: The Holloway Cut Advisor (HCA) is a patented online tool that provides indications of potential diamond performance based upon a few basic measurements. It is intended to be a basic screening tool to reject diamonds likely to have performance deficits.; Learn More …

HEART CUT

What is Heart Cut?

: The heart cut, or heart shape, is a brilliant cut diamond shaped like a heart, pointed at one end with two rounded edges separated by a “V” at the other.; Learn More …

HEART SHAPE

What is Heart Shape?

: The heart shape, or heart cut is a brilliant cut diamond shaped like a heart, pointed at one end with two rounded edges separated by a “V” at the other.; Learn More …

HEARTS & ARROWS CUT

What is Hearts & Arrows?

: A hearts and arrows diamond is a modern round brilliant, cut with a goal of 3D optical precision. When successful, the facet reflections overlap and a crisp pattern of “hearts and arrows” is seen in a special viewer.; Learn More …

HELIUM

What is Helium Scanner?

: The Helium scanner, by Octonus, is a sophisticated piece of technology, capable of measuring and modeling polished and rough diamonds.; Learn More …

HRD

What is HRD?

: HRD stands for Hoge Raad voor Diamant, a gemological laboratory established in Antwerp, Belgium with offices in several major international markets.; Learn More …

HTHP

What is HPHT?

: In lab grown diamond creation, HPHT stands for High Pressure, High Temperature. This process replicates the conditions under which natural diamonds are formed. It employs anvils, heating and pressure apparatus applying significant pressure and heat to a small cell over a period of days or weeks.; Learn More …

HUE

What is Hue?

: A stone’s hue is its primary color impression, such as red, green, or blue.; Learn More …

I (INCLUDED) GRADE

What is I3?

: I3 is the lowest diamond clarity grade, frequently implying issues with transparency, durability, or both.; Learn More …

IDEAL

What is Ideal Cut?

: Ideal cut refers to a set of proportions for a round brilliant diamond which produce the most desirable optical effects. An ideal cut diamond will have the word “ideal” printed on its laboratory grading report.; Learn More …

IDEAL SCOPE

What is Ideal Scope?

: The Ideal Scope is a cut quality assessment tool for round diamonds. Its translucent cone and magnifying lens create a structured light environment which reveal areas of brightness, leakage, and contrast when placed over a diamond.; Learn More …

IF (INTERNALLY FLAWLESS) GRADE

What is IF?

: A gemstone with no characteristics visible at 10 power magnification, is considered flawless (FL), and a gemstone with surface blemishes but no inclusions can be graded internally flawless (IF).; Learn More …

IGI

What is IGI?

: IGI (International Gemological Institute) is the world’s largest gemological organization, with 18 laboratories and 14 schools of gemology around the world. IGI pioneered the grading of lab grown diamonds in 2005, and became the first to commit to carbon neutrality in 2020.; Learn More …

ILLUSION SETTING

What is Illusion Setting?

: An illusion setting surrounds the stone to make it appear larger.; Learn More …

INCLUSION

What is Inclusion?

: An inclusion is a clarity characteristic that is internal, within a gemstone. Surface characteristics are classified as blemishes.; Learn More …

INDENTED NATURAL

What is Indented Natural?

: An indented natural is a portion of the rough diamond’s original surface that dips below a polished diamond’s surface.; Learn More …

INSCRIPTION

What is Inscription?

: An inscription is a series of characters laser-inscribed onto a diamond, typically on its girdle, frequently correlating to its laboratory grading report.; Learn More …

INSURANCE

What is Insurance?

: Engagement ring insurance is designed as a safety net in case of loss, damage, or theft of your engagement ring. Like auto insurance there are many different insurers and options.; Learn More …

INTERNAL GRAINING

What is Internal Graining?

: Graining may appear within a diamond as lines showing the crystal structure’s growth pattern. Graining can be external or internal.; Learn More …

INVISIBLE SETTING

What is Invisible Setting?

: Invisible setting is a style where square or rectangular diamonds are mounted next to each other without any visible metal holding them in place, creating the appearance of a solid surface of stones.; Learn More …

IRRADIATION

What is Irradiation?

: Irradiation is a diamond treatment technique which alters its color by bombarding it with radiation.; Learn More …

KARAT

What is Karat?

: Karat (k) is the unit of measure for the weight and purity of gold and gold alloys.; Learn More …

KEEL

What is Keel?

: A keel is the equivalent of a culet on a non-brilliant style faceted diamond, forming a line on the bottom of the pavilion, rather than a point.; Learn More …

KIMBERLEY PROCESS

What is Kimberley Process?

: The Kimberley Process (KP or KPCS) is a certification system developed and implemented by the United Nations to prevent and discourage the flow of conflict diamonds and gemstones.; Learn More …

KIMBERLITE

What is Kimberlite?

: A Kimberlite is a pipe-shaped mixture of rock material, formed by solidifying volcanic magma. Kimberlites are not the source of diamonds, they are the “elevator” which brings them to the Earth’s surface.; Learn More …

KNIFE EDGE

What is Knife Edge?

: A knife edge is a decorative element on a setting, where the edge of the band tapers coming to a slight point or knife.; Learn More …

KNOT

What is Knot?

: A knot is an inclusion type, where one diamond crystal has become lodged within a larger diamond crystal.; Learn More …

LAB REPORT

What is Lab Report?

: A lab report, or grading report is one that has been issued by a grading laboratory, providing their judgment on the characteristics and quality of a gemstone.; Learn More …

LAB-CREATED DIAMOND

What is Lab Created Diamond?

: Lab-created diamonds, or lab grown diamonds, are produced in factories using sophisticated chemical synthesis over a period of 1-4 weeks. Aside from subtle carbon distinctions a lab grown diamond is optically and chemically identical to a natural diamond.; Learn More …

LAB-GROWN DIAMOND

What is Lab Grown Diamond?

: Lab grown diamonds, are produced in factories using sophisticated chemical synthesis over a period of 1-4 weeks. Aside from subtle carbon distinctions a lab grown diamond is optically and chemically identical to a natural diamond.; Learn More …

LASER DRILL (HOLE)

What is Laser Drill Hole?

: A laser drill hole is a tiny tube into a diamond, made by a laser to remove an inclusion. The surface opening may resemble a pit, while the tube usually looks needle like.; Learn More …

LASER DRILLING

What is Laser Drilling?

: Laser drilling refers to techniques designed to improve a diamond’s clarity by vaporizing an inclusion or creating a path to it for acid which can dissolve it.; Learn More …

LASER IDENTIFICATION

What is Laser Identification?

: Laser identification refers to a series of characters laser-inscribed onto a diamond, typically on its girdle, frequently correlating to its laboratory grading report.; Learn More …

LEAKAGE

What is Leakage?

: Light entering a gemstone from above will either reflect and return back up to the viewer’s eyes (as brightness) or escape through the bottom (as leakage or windowing). In general terms, brightness is desirable, leakage is to be avoided, with some exceptions.; Learn More …

LENGTH TO WIDTH RATIO

What is Length to Width Ratio?

: Length to width (L/W) ratio is found by dividing the length of the gemstone by the width. The width is always stated as 1.; Learn More …

LIGHT LEAKAGE

What is Light Leakage?

: Light entering a gemstone from above will either reflect and return back up to the viewer’s eyes (as brightness) or escape through the bottom (as leakage or windowing). In general terms, brightness is desirable, leakage is to be avoided, with some exceptions.; Learn More …

LIGHT MAP

What is Light Map?

: A light map is a computer generated graphic which gives information about the diamond’s light performance.; Learn More …

LIGHT PERFORMANCE

What is Light Performance?

: Light performance refers to the collective appearance of a diamond’s optical beauty components.; Learn More …

LIGHT RETURN

What is Light Return?

: Light entering a gemstone from above will either reflect and return back up to the viewer’s eyes (as brightness) or escape through the bottom (as leakage or windowing). In general terms, light returning as brightness is desirable, leakage is to be avoided, with some exceptions.; Learn More …

LOUPE

What is Loupe?

: A loupe is a small magnifying lens used by gemstone and jewelery professionals. The standard magnification is 10X, but loupes are available in 20X, 30X and higher powers.; Learn More …

LOUPING

What is Louping?

: Louping refers to the process of analyzing a gemstone or jewelry with a jeweler’s loupe.; Learn More …

LOWER GIRDLE

What is Lower Girdle Facet?

: Lower girdle facets, also called half-facets, are the pairs of facets below the girdle and between the pavilion mains.; Learn More …

MAINS

What is Mains?

: The main facets are the pavilion mains, which extend all the way from the girdle to the culet on the pavilion, and the bezel/kite/crown main facets, which extend from the girdle to the table on the crown.; Learn More …

MAKE

What is Make?

: Make refers to the diamond’s cut quality. The better the make, the better the diamond.; Learn More …

MANDREL

What is Mandrel?

: A jeweler’s mandrel is a tool used to determine the size of an existing ring. Be advised that differences are possible between ring mandrels, even those that come from the same manufacturer.; Learn More …

MARQUISE

What is Marquise?

: Sometimes referred to as a navette cut, the marquise cut diamond was originally fashioned for King Louis XIV. It reached incredible popularity in the late 1900s and can frequently be found second-hand, in jewelry stores and estate sales.; Learn More …

MARQUISE SHAPE

What is Marquise Shape?

: Sometimes referred to as a navette cut, the marquise cut diamond was originally fashioned for King Louis XIV. It reached incredible popularity in the late 1900s and can frequently be found second-hand, in jewelry stores and estate sales.; Learn More …

MATCHED SET

What is Matched Set?

: A matched set is a pair of diamonds with identical or near-identical carat weight, color, clarity and cut proportions.; Learn More …

MATCHING SET

What is Matching Set?

: When referring to jewelry a matching set usually refers to an engagement ring and wedding band that were designed to go together.; Learn More …

MAZAL

What is Mazal?

: Mazal, short for mazal tov, is a Hebrew term, often used in the diamond trade when a deal between two people is agreed upon.; Learn More …

MELEE

What is Melee?

: Melee refers to small diamonds under 0.20 carat, and most often 0.10 carat or below, which may have 57 facets (full cut) or 17 facets (single cut).; Learn More …

MICRO-PAVÉ

What is Micro Pave?

: A pave or pavé (pronounced pah-vay) setting uses many small stones set close together, looking like the piece is paved in gemstones. A micro-pavé setting is similar, but uses even smaller diamond and beads, leaving very little metal exposed.; Learn More …

MILGRAIN OR BEADING

What is Milgrain?

: Beading or milgrain is representative of little ‘beads’ of metal used to accent the edge of a setting or its design features like the halo, bezel or as a pattern to add additional adornment to the style.; Learn More …

MINE CUT DIAMOND

What is Mine Cut?

: Sometimes called an old mine cut (OMC), an early form of the round brilliant diamond with a squarish-shaped girdle, high crown, small table, deep pavilion, and very large culet.; Learn More …

MINING

What is Mining?

: Diamond mining uses heavy mechanized excavation of diamond bearing volcanic pipes (primary mining), artisanal digging (alluvial mining) and processing of deposits at the coast and on the sea floor (marine mining).; Learn More …

MIXED-CUT

What is Mixed Cut?

: A mixed cuts combines brilliant (kite shaped) and step (rectangular shaped) facets, combining the aesthetics of both styles.; Learn More …

MOHS SCALE

What is Mohs Scale?

: The Mohs scale of mineral hardness was created in 1812 by the German geologist and mineralogist Friedrich Mohs. It characterizes the scratch resistance of various minerals through the ability of a harder material to scratch a softer material. Diamond is the hardest known substance, scoring 10 on the Mohs scale.; Learn More …

MOHS SCALE OF HARDNESS

What is Mohs Scale of Hardness?

: The Mohs scale of mineral hardness was created in 1812 by the German geologist and mineralogist Friedrich Mohs. It characterizes the scratch resistance of various minerals through the ability of a harder material to scratch a softer material. Diamond is the hardest known substance, scoring 10 on the Mohs scale.; Learn More …

MOISSANITE

What is Moissanite?

: Synthetic moissanite is a modern diamond simulant with good hardness and dispersion. It can fool the simple thermal conductivity probes used to easily detect cz and most other simulants. However, it is doubly refractive, allowing it to be identified with the trained eye.; Learn More …

MOUNTING

What is Mounting?

: A mounting is a jewelry item into which a central gemstone may be set.; Learn More …

NAIL HEAD

What is Nail Head?

: A nail head refers to a diamond that is extremely deep and appears dark in the center.; Learn More …

NATURAL

What is Natural?

: A natural refers to original rough on an otherwise polished gemstone’s surface, usually found at the girdle.; Learn More …

NEEDLE

What is Needle?

: A needle is a clarity term describing a long, thin crystal inclusion within a gemstone.; Learn More …

NICK

What is Nick?

: A nick is a clarity term describing a minor chip or break on the gemstone’s surface.; Learn More …

OBSCURATION (HEAD SHADOW)

What is Obscuration?

: Obstruction, or obscuration, refers to the effect of a viewer on the diamond, when light from above is blocked by the head. It is closely related to contrast, a positive performance component.; Learn More …

OBSTRUCTION

What is Obstruction?

: Obstruction, or obscuration, refers to the effect of a viewer on the diamond, when light from above is blocked by the head. It is closely related to contrast, a positive performance component.; Learn More …

OFF MAKE

What is Off Make?

: An off make diamond is one which is poorly proportioned.; Learn More …

OGI

What is OGI?

: OGI Systems is a manufacturer of diamond scanning technologies.; Learn More …

OLD EUROPEAN CUT

What is Old European Cut?

: The old European cut (OEC) is a predecessor to the modern round brilliant, featuring a small table, a high crown and wide pavilion main facets.; Learn More …

OLD MINE CUT

What is Old Mine Cut?

: The old mine cut (OMC), is an early form of the round brilliant diamond with a squarish-shaped girdle, high crown, small table, deep pavilion, and very large culet.; Learn More …

OPAQUE

What is Opaque?

: An opaque characteristic within a gemstone is neither transparent nor translucent, so typically more visible.; Learn More …

OPTICAL PRECISION

What is Optical Precision?

: Optical precision describes how precisely groups of corresponding facets align with each other in 3 dimensional space.; Learn More …

OPTICAL SYMMETRY

What is Optical Symmetry?

: Optical precision describes how precisely groups of corresponding facets align with each other in 3 dimensional space. Because it is sometimes confused with the “meet point” symmetry graded on a diamond report, a better term is optical precision.; Learn More …

OVAL CUT

What is Oval Cut?

: The oval cut diamond has brilliant facets, providing sparkle and brightness in an elongated shape that sets it apart from a round brilliant.; Learn More …

OVAL SHAPE

What is Oval Shape?

: The oval shape diamond has brilliant facets, providing sparkle and brightness in an elongated shape that sets it apart from a round brilliant.; Learn More …

PALLADIUM

What is Palladium?

: Palladium is a noble metal, similar to platinum, which is dense, strong and hypoallergenic.; Learn More …

PAVE

What is Pave?

: A pave or pavé (pronounced pah-vay) setting uses many small stones set close together, looking like the piece is paved in gemstones.; Learn More …

PAVILION

What is Pavilion?

: The pavilion is the bottom section of a polished diamond or colored gemstone, below the girdle of the stone.; Learn More …

PAVILION ANGLE

What is Pavilion Angle?

: The pavilion angle is created by the intersection of the girdle and the main pavilion facet.; Learn More …

PAVILION MAIN FACET

What is Pavilion Main Facet?

: The pavilion mains extend all the way from the girdle to the culet on a diamond.; Learn More …

PEAR

What is Pear Cut?

: The pear cut diamond is a timeless cut with the brilliant style of faceting and a unique shape aesthetic. Though traditionally worn with the tip pointing at the wearer’s heart, the pear cut may be set and worn in a variety of ways.; Learn More …

PEAR CUT

What is Pear Shape?

: The pear shape diamond is a timeless cut with the brilliant style of faceting and a unique shape aesthetic. Though traditionally worn with the tip pointing at the wearer’s heart, the pear cut may be set and worn in a variety of ways.; Learn More …

PENDANT

What is Pendant?

: A pendant is a piece of jewelry that typically hangs from a chain worn around the neck.; Learn More …

PENDELOQUE CUT

What is Pendeloque Cut?

: A pendeloque cut, credited to Louis de Berquem in the 15th century, is a pear-shaped modification of the round brilliant cut used for diamonds.; Learn More …

PHOSPHORESCENCE

What is Phosphorescence?

: Phosphorescence is a rare property in diamonds. When exposed to strong ultraviolet wavelengths a phosphorescent diamond will continue to emit light for a period of time after the light source is removed.; Learn More …

PINK

What is Pink Diamond?

: Pink is an extremely rare color in natural diamonds. The color is generally thought to be caused by colored graining, which results from structural irregularities in combination with an impurity. Distortions in the crystal structure are thought to be the cause of color for 99.5% of pink diamonds.; Learn More …

PINPOINTS

What is Pinpoint?

: Pinpoints are very small inclusions in a diamond. A cluster of pinpoints can form a cloud.; Learn More …

PIQU’E

What is Pique?

: Pique (pronounced pee-kay) is a trade term used to describe a visible inclusion within a gemstone.; Learn More …

PIT

What is Pit?

: A pit is a clarity term describing a tiny surface opening, resembling a white dot, with no apparent depth.; Learn More …

PLATINUM

What is Platinum?

: Platinum is a dense, strong durable and hypoallergenic metal used in jewelry.; Learn More …

PLOT

What is Plot?

: A plot is a diagram that appears on most laboratory reports detailing the location and type of clarity characteristics reported.; Learn More …

POINT

What is Point?

: A point is equivalent to one-hundredth of a carat. A 0.70 carat diamond would is typically called a 70-point diamond.; Learn More …

POLISH

What is Polish?

: Polish and symmetry are component of finish, judged when assessing the cut quality of a diamond. Polish refers to the smoothness of each facet of a diamond.; Learn More …

POLISH LINES

What is Polish Line?

: Polish lines are parallel grooves and ridges left on a gem’s facet as a result of the polishing process, considered blemishes.; Learn More …

POLISH MARK

What is Polish Mark?

: A polish mark, also called a burn mark, is surface clouding caused by excessive heat during polishing.; Learn More …

POOR CUT

What is Poor Cut?

: Poor cut is the fifth or sixth category on the cut grading scale: (Ideal), Excellent, Very Good, Good, Fair, Poor.; Learn More …

PRICE-PER-CARAT

What is PPC?

: Price-per-carat (PPC) is the diamond’s price divided by its carat weight. PPC is useful for comparing diamonds of similar, but not identical, carat weights.; Learn More …

PREMIER

What is Premier Mine?

: The Premier mine was established in South Africa. On its 100th anniversary the name of the mine was changed to the Cullinan, in recognition of the Cullinan Diamond, the largest ever found, which was mined there.; Learn More …

PRESENTATION SOLITAIRE

What is Presentation Ring?

: A presentation ring is a temporary setting, permitting a gemstone to be presented as a gift for which the recipient can determine final setting style.; Learn More …

PRICE-PER-CARAT

What is Price Per Carat?

: Price-per-carat (PPC) is the diamond’s price divided by its carat weight. PPC is useful for comparing diamonds of similar, but not identical, carat weights.; Learn More …

PRINCESS

What is Princess Cut?

: Princess cut diamonds use the brilliant cutting style on the pavilion to achieve scintillation in a square shape.; Learn More …

PRONG

What is Prong?

: A prong is a metal tip, several of which are used to hold a gemstone in place. Prongs can be shaped in different styles.; Learn More …

PRONG OR CLAW SETTING

What is Prong Setting?

: A prong setting typically includes four or six prongs which hold a central gemstone in place.; Learn More …

PROPORTIONS

What is Proportions?

: A diamond’s proportions are measurements of its overall geometry, facet angles and relationships. The way proportions work together determines how light behaves when it enters that diamond.; Learn More …

RADIANCE

What is Radiance?

: Radiance is a word sometimes used to describe the dynamic light performance of a diamond.; Learn More …

RADIANT CUT

What is Radiant Cut?

: The radiant cut diamond is a mixed cut which was developed by Henry Grossbard family in 1977. It offers dazzling fire and brilliance and the cut corners create a shape aesthetic that pairs well with either round or square shapes.; Learn More …

RAPAPORT

What is Rapaport?

: Rapaport is a wholesale pricing guide, published monthly, that is used by many within the trade to barter buying and selling prices of natural polished diamonds.; Learn More …

RAY TRACING

What is Ray Tracing?

: Ray tracing uses a 3D model of a diamond, imported into software designed to follow the light as it travels through the diamond, taking its total sculpture into account.; Learn More …

REFRACTION

What is Refraction?

: The bending of light into its component spectral colors, as it passes through a diamond or gemstone.; Learn More …

REFRACTIVE INDEX OR INDEX OF REFRACTION

What is Refractive Index?

: The refractive index determines how much light is bent, or refracted, when entering a material.; Learn More …

RHINESTONE (FOIL BACK)

What is Rhinestone?

: Rhinestone is an early diamond simulant, created by backing cut glass with a reflective paint.; Learn More …

RHODIUM PLATING

What is Rhodium Plating?

: White gold is typically yellow gold with rhodium plating. Rhodium plated rings can be re-plated as needed due to wear.; Learn More …

RIVER

What is River Color?

: River is an old world term for the most colorless diamond.; Learn More …

ROSE CUT

What is Rose Cut?

: A rose cut is a stone cut with a flat base, where the upper facets rise to a point, encountered in antique jewelry starting with the 17th century.; Learn More …

ROUGH

What is Rough Diamond?

: A rough diamond is a natural or lab grown diamond that has yet to be cut or polished.; Learn More …

ROUND BRILLIANT

What is Round Brilliant?

: The round brilliant cut is the most popular among producers, because it maximizes yield, and among consumers because it’s most efficient and reflecting and returning light to the viewer’s eyes.; Learn More …

SAMPLE IMAGE

What is Sample Image?

: A sample image is one that is supposed to represent the diamond, gemstone or jewelry item shown, but is not an image of the actual item that’s offered for purchase or described. Used when the seller does not have the actual image available, and with mass-produced jewelry pieces.

SARINE

What is Sarine?

: Sarine is a diamond industry technology provider, producing highly accurate non-contact measuring devices. A Sarine scan (.SRN) can be used in different software programs to determine proportions, analyze faceting and symmetry and generate technical CGI for a diamond.; Learn More …

SATURATION

What is Saturation?

: Saturation is the measure of how strong and intense the primary color of the diamond actually is, such as light, deep, intense or vivid; Learn More …

SCINTILLATION

What is Scintillation?

: Scintillation, also called sparkle, is the suite of white and colored flashes and dynamic bright and dark areas seen when the diamond, the viewer or the light source are in motion.; Learn More …

SCRATCH

What is Scratch?

: A linear abrasion on the surface of a diamond with no apparent depth.; Learn More …

SHALLOW CUT

What is Shallow Cut?

: A shallow diamond is one where narrow cutting angles were used. The positive aspect is greater physical spread, the negative aspect can be darkness when a viewer draws close.; Learn More …

SHAPE

What is Shape?

: A diamond’s shape refers to its geometric outline, such as round, pear or oval. It is sometimes mistaken for cut, which refers to the finish and proportions of a diamond or gemstone.; Learn More …

SIGHT HOLDER

What is Sightholder?

: A sightholder is a major diamond producer who has been extended permission to purchase rough diamonds directly from one of the major mining houses, like ALROSA or DeBeers.; Learn More …

SIMULANT

What is Simulant?

: A simulant has an appearance similar to that of a natural gemstone, but has different optical, physical, and chemical properties. Examples of diamond simulants are CZ and Moissanite.; Learn More …

SINGLE CUT

What is Single Cut?

: Also called eight cut, a single cut diamond has only eight pavilion mains and eight crown mains, for a total of 17 facets. Eight cut is usually restricted to melee (very small diamonds).; Learn More …

SOLITAIRE

What is Solitaire?

: A solitaire ring has a single diamond or stone set by itself in mounting.; Learn More …

SPARKLE

What is Scintillation?

: Sparkle, also called scintillation, is the suite of white and colored flashes and dynamic bright and dark areas seen when the diamond, the viewer or the light source are in motion.; Learn More …

SPLIT SHANK

What is Split Shank?

: A split shank engagement ring is a style where the shank, or band, splits open towards the center stone creating two or more arms that support the head.; Learn More …

SPREAD

What is Spread?

: A diamond’s physical spread is the average of its length and width in millimeters.; Learn More …

SPREAD CUT

What is Spready?

: A spready stone or spready diamond is one with a large table and shallow depth.; Learn More …

STACKING OR STACKED SET

What is Stacking Set?

: A stacked set is one where multiple bands or rings are stacked together, or an engagement ring paired and ‘sandwiched’ between two or more bands.; Learn More …

STAR

: The small triangular facets between the table and the upper girdle facets.; Learn More …

STAR FACET

What is Star Facet?

: The star facets on a round brilliant diamond are the eight triangular facets connecting the table to the kite or bezel facets.; Learn More …

STEEP/DEEP

What is Steep-Deep?

: A steep-deep diamond is one where wide cutting angles was used to increase the diamond’s final weight, maximizing yield. Those wide angles cause some of the light entering the diamond to leak out of the bottom, instead of reflecting and returning to the viewer’s eyes. When removed from bright lights, steep deep diamonds quickly go dark and look physically smaller than they should.; Learn More …

STEP CUT

What is Step Cut?

: Step cut describes a cutting style which features long, narrow facets in rows, running parallel to the girdle on both the crown and pavilion. The emerald cut is the most popular step cut.; Learn More …

STONTIUM TITANATE

What is Stontium Titanate

: Stontium titanate is an early diamond simulant, from the 1950’s, that featured very high dispersion but was too soft on the Mohs scale (5.5) to be durable.; Learn More …

SUPER IDEAL

What is Super Ideal?

: The PriceScope definition of Super Ideal is a diamond cut within a small range of scientifically proven “ideal” proportions which promote balanced brightness, fire, sparkle, and contrast. Beyond those basic proportions, the internal reflections are further fine-tuned to display 3D optical precision (aka Hearts & Arrows), proven in a specialized viewer.; Learn More …

SURFACE GRAINING

What is Surface Graining?

: Graining may appear on a diamond’s surface as lines showing the crystal structure’s growth pattern. Graining can be external or internal.; Learn More …

SYMMETRY

What is Symmetry?

: Symmetry refers to the shape, uniformity and meet points of a diamond’s surface facets and the alignment of facet groups from crown to pavilion around the entire compass of the diamond.; Learn More …

SYNTHETIC

What is Synthetic?

: A synthetic gemstone is one produced by humans with optical, physical and chemical properties which are identical to its natural counterpart. A synthetic gemstone is “real, ” unlike a simulant, which is a different material, created to simulate a gemstone’s properties.; Learn More …

SYNTHETIC DIAMOND

What is Synthetic Diamond?

: A synthetic diamond, more commonly called a lab grown diamond, is one produced by humans with optical, physical and chemical properties which are identical to natural diamonds. A synthetic diamond is “real, ” unlike a simulant, which is a different material, created to simulate a diamond’s properties.; Learn More …

TABLE

What is Table?

: The table facet is the topmost, flat, horizontal facet that appears on polished and faceted diamonds and colored gemstones.; Learn More …

TABLE %

What is Table %?

: The table percentage (table %) is expressed as a percentage of the total diameter of the diamond.; Learn More …

TABLE CUT

What is Table Cut?

: The table cut is a very early diamond cut, created by grinding down one point of a rough octahedral diamond crystal, creating a large flat facet, with the other natural crystal faces intact.; Learn More …

TABLE FACET

What is Table Facet?

: The table facet is the topmost, flat, horizontal facet that appears on polished and faceted diamonds and colored gemstones.; Learn More …

TABLE PERCENTAGE

What is Table Percentage?

: The table percentage (table %) is expressed as a percentage of the total diameter of the diamond.; Learn More …

TABLE SIZE

What is Table Size?

: Table size is determined by measuring a round brilliant diamond’s table in four directions and dividing by four.; Learn More …

TABLE SPREAD

What is Table Spread?

: Term used to describe the width of the table facet, expressed as a percentage of the total diameter of the stone.; Learn More …

TENSION SETTING

What is Tension Setting?

: A tension setting uses pressure to hold a stone by squeezing its girdle between open ends of the setting, creating the illusion that the stone is floating.; Learn More …

THE 4 CS

What is The 4Cs?

: The Diamond 4Cs are Carat weight, Color, Clarity and Cut.; Learn More …

THREE STONE RING

What is Three Stone Ring?

: A three stone ring is often given as an anniversary band representing the past, present and future, however, they can also be worn as an engagement or cocktail ring. Three stone rings allow the wearer to mix and match stone shapes or colors to create a personalized design.; Learn More …

TOLKOWSKY

What is Tolkowsky?

: Marcel Tolkowsky was a mathemetician who calculated optimum proportions for light behavior in a round diamond in 1919. Referred to as Tolkowksy Ideal Cut, much of his work has been validated by modern grading systems.; Learn More …

TONE

What is Tone?

: Tone refers to how light or dark a color appears.; Learn More …

TOP WESSELTON

What is Top Wesselton?

: Top Wesselton is an old world term which refers to colours F and G on the diamond color scale.; Learn More …

TOUGHNESS

What is Toughness?

: Toughness describes a gemstone’s ability to resist breakage.; Learn More …

TRANSITIONAL CUT

What is Transitional Cut?

: Transitional cuts are styles which followed the old mine and old European cuts as precursors of the modern round brilliant, featuring a larger table and lower crown.; Learn More …

TRANSPARENCY

What is Transparency?

: Transparency is a measure of the effective transmission of light through a diamond or colored gemstone.; Learn More …

TRAPEZOID

What is Trapezoid?

: A trapezoid is a four sided step cut with two sides of uneven length, usually seen as side stones for a straight-sided center stone.; Learn More …

TREATED DIAMONDS

What is Treated Diamond?

: A treated diamond has had its color or clarity artificially enhanced, through use of laser drilling, fracture filling, spot bleaching by laser, coating, HPHT (high pressure high temperature) whitening, electromagnetic conduction whitening or other process.; Learn More …

TRIANGLE CUT

What is Triangle Cut?

: A triangle-cut diamond is one with three sides, which resembles a triangle.; Learn More …

TRILLIANT

What is Trilliant?

: The trillion cut diamond, also known as the triangular brilliant, trillion and trilliant, is a bright and lively cut. These diamonds work well as side stones to accentuate a variety of diamond shapes but can also look spectacular as a solitaire.; Learn More …

TRILLION SHAPE

What is Trillion Cut?

: The trillion cut diamond, also known as the triangular brilliant, trillion and trilliant, is a bright and lively cut. These diamonds work well as side stones to accentuate a variety of diamond shapes but can also look spectacular as a solitaire.; Learn More …

TRIPLE EX

What is Triple Ex?

: A Triple EX, or 3EX diamond is one with an excellent cut grade, along with excellent polish and excellent symmetry.; Learn More …

TRIPLE 0

What is Triple 0?

: A triple zero, triple 0 or 000 diamond refers to one graded by the American Gem Society, with the top grade of 0 (zero) in Performance or Proportions, Symmetry and Polish. It originally referred to a diamond with top grades in color, clarity and cut, but that interpretation is rarely used.; Learn More …

TRIPLE ZERO

What is Triple Zero?

: A triple zero, triple 0 or 000 diamond refers to one graded by the American Gem Society, with the top grade of 0 (zero) in Performance or Proportions, Symmetry and Polish. It originally referred to a diamond with top grades in color, clarity and cut, but that interpretation is rarely used.; Learn More …

TWINNING WISP

What is Twinning Wisp?

: A twinning wisp is a series of pinpoints, clouds, or crystals that forms in a diamond’s growth plane, associated with crystal distortion and twinning planes.; Learn More …

ULTRAVIOLET LIGHT

What is Ultraviolet Light?

: Ultraviolet (UV) light is light that is not visible to the naked eye because its wavelengths are shorter than wavelengths of visible light. Gemstones are tested for fluorescence and phosphorescence using short wave and long wave UV light.; Learn More …

UPPER-GIRDLE FACET

What is Lower Girdle Facet?

: Upper girdle facets, also called half-facets, are the pairs of facets between the girdle and the crown main (bezel or kite) facets.; Learn More …

VARIETY

What is Variety?

: A variety is a subcategory of mineral species. For instance, rubies are a variety of the mineral species corundum.; Learn More …

VERY GOOD CUT (PREMIUM)

What is Very Good Cut?

: Very Good cut is the third or fourth category on the cut grading scale: (Ideal), Excellent, Very Good, Good, Fair, Poor.; Learn More …

ANTIQUE OR VINTAGE

What is Vintage Ring?

: Antique or vintage rings are designs influenced by past style trends. These designs may include such details as beading, milgrain, art deco influences, engraving, scallop or scroll work and pavé set diamonds.; Learn More …

VIRTUAL FACET

What is Virtual Facet?

: A virtual facet is an individual light event within a diamond, which can be part or all of any given facet. The size, number and distribution of virtual facets is the key to light performance.; Learn More …

VPA

What is VPA?

: VPA stands for Visual Proportion Analyzer, a software program from AGS that uses a 3D scan of a diamond to graphically display nuanced details of its cut quality and optical precision.; Learn More …

VS (VERY SLIGHTLY INCLUDED) GRADE

What is VS?

: VS (Very Slightly Included) clarity grade is between VVS and SI, and is divided into levels VS1 and VS2. Diamonds with these grades fall into the upper half of the diamond clarity range and are usually completely clean to the unaided eye.; Learn More …

VVS (VERY VERY SLIGHTLY INCLUDED) GRADE

What is VVS?

: The VVS (Very Very Slightly Included) clarity grade is between Flawless and VS. VVS diamonds land in the rare collection category when paired with D, E or F color and a top cut grade.; Learn More …

WEDDING SET

What is Wedding Set?

: A wedding set is an engagement ring and wedding band which go together, and can be a deliberately matched set or a mixed set.; Learn More …

WEIGHT RATIO

What is Weight Ratio?

: Weight ratio is a calculation of diamond’s overall weight in relation to its diameter, also known as spread.; Learn More …

WELL CUT

What is Well Cut?

: The PriceScope definition of well cut is known as the PriceScope Ideal: A diamond cut with proportionate angles which successfully reflect and return light back to the viewer’s eyes as brightness, fire, contrast, and sparkle.; Learn More …

WESSELTON

What is Wesselton?

: Wesselton is an old world description of a diamond with H color, and was originally the name of a diamond mine producing high colored diamonds.; Learn More …

WHITE GOLD

What is White Gold?

: White gold is frequently yellow gold plated with rhodium, but some white gold is also produced unplated, alloyed with metals such as iridium and palladium.; Learn More …

X-RAY FLUORESCENCE

What is X-Ray Fluorescence?

: X-Ray Fluorescence refers to a diamond’s ability to emit secondary x-rays when it is exposed to x-rays. This characteristic is used to identify diamonds, and separate them from other stones, by exciting their chemical elements.; Learn More …

YAG

What is YAG?

: YAG (Yttrium Aluminum Garnet) is a lab grown material that was used as an early diamond simulant.; Learn More …

YIELD

What is Yield?

: Yield refers to the weight of a finished gemstone after it’s polished from a rough stone.; Learn More …