shape
carat
color
clarity

New to coloured gemstone buying? Read this first!

SPSGuy

Rough_Rock
Joined
Sep 7, 2014
Messages
7
Excellent post, the detail of purchasing a stone boggles the mind.
 

cutratediamonds

Rough_Rock
Trade
Joined
Oct 28, 2014
Messages
15
Very good post..!! Helpful for the newbies.. :)
 

Trademan14

Rough_Rock
Joined
Dec 1, 2014
Messages
1
Wow!!! Very helpful, thank you so much for this informative post!!!
 

amazingAkj

Rough_Rock
Joined
May 21, 2015
Messages
6
Hey chrono, can you post pictures of whatever you have mention in your post so that it will be easy to recognize?
 

chrono

Super_Ideal_Rock
Premium
Joined
Apr 22, 2004
Messages
38,364
amazingAkj|1432296687|3879995 said:
Hey chrono, can you post pictures of whatever you have mention in your post so that it will be easy to recognize?
Can you please be more specific? I've posted a lot of things. :lol: I do try to post links to studies/papers wherever possible.
 

Abzurd

Rough_Rock
Joined
May 23, 2015
Messages
1
Hi, I'm new to the world of coloured stones. During recent travels been exposed to tourmaline and emerald and decided I will learn and maybe create opportunity out of what has presented itself to me... Learnt a fair bit already in a short space of time...
 

LD

Super_Ideal_Rock
Premium
Joined
Jun 29, 2008
Messages
10,261
Abzurd|1432366364|3880357 said:
Hi, I'm new to the world of coloured stones. During recent travels been exposed to tourmaline and emerald and decided I will learn and maybe create opportunity out of what has presented itself to me... Learnt a fair bit already in a short space of time...

Abzurd - I'm glad to hear that you're enjoying the learning. Actually you'll find that won't stop because there's always new things to learn (especially about treatments) to keep us on our toes! We can't relax! :)
 

chrono

Super_Ideal_Rock
Premium
Joined
Apr 22, 2004
Messages
38,364
Gem lab listing

USA
AGL is the top choice.
GIA is also good.

Europe
SSEF, Gubelin and GIA are the top choices.
Chris Dunaigre, GGTL and GRS are also good.

Asia
SSEF, Gubelin (mobile lab), Lotus Gemology and GIA are top choices.
For all else, as long as they aren't corundum (sapphire or ruby) which requires better equipment = AIGS, GIT, Burapha, Tokyo Gem Lab, Emil Gem Lab, Nanyang Gem Institute
 

userangl28212003

Brilliant_Rock
Premium
Joined
Jan 26, 2014
Messages
1,018
Chrono|1437659749|3906462 said:
Gem lab listing

USA
AGL is the top choice.
GIA is also good.

Europe
SSEF, Gubelin and GIA are the top choices.
Chris Dunaigre, GGTL and GRS are also good.

Asia
SSEF, Gubelin (mobile lab), Lotus Gemology and GIA are top choices.
For all else, as long as they aren't corundum (sapphire or ruby) which requires better equipment = AIGS, GIT, Burapha, Tokyo Gem Lab, Emil Gem Lab, Nanyang Gem Institute
Doesn't AIGS have better equiptment now for testing rubies and sapphires?
 

Niel

Super_Ideal_Rock
Premium
Joined
Jul 23, 2012
Messages
20,044
Chrono|1437659749|3906462 said:
Gem lab listing

USA
AGL is the top choice.
GIA is also good.

Europe
SSEF, Gubelin and GIA are the top choices.
Chris Dunaigre, GGTL and GRS are also good.

Asia
SSEF, Gubelin (mobile lab), Lotus Gemology and GIA are top choices.
For all else, as long as they aren't corundum (sapphire or ruby) which requires better equipment = AIGS, GIT, Burapha, Tokyo Gem Lab, Emil Gem Lab, Nanyang Gem Institute

I see grs used more than I used to. Is it just that it's uncommon in the US? Or is it really better outside the US than in?
 

Johndev478

Rough_Rock
Joined
Jan 24, 2016
Messages
1
Wow, what an informative post. Really helpful for those who are new to buy gemstones. Much more important things are described here. I bought amber stones from "Drfinejewels.com",which is a good wholesaler company registered in the Dominican Republic. There you can find all type and color of stone. Thanks a lot.........
 

garyhsu

Rough_Rock
Joined
Jan 28, 2016
Messages
3
Fabulous post.

Loved it!

Thanks,
:angel:
 

Lisa Loves Shiny

Ideal_Rock
Premium
Joined
Nov 1, 2007
Messages
4,685
Great Post! I would like to add some red flags that need to be investigated by potential buyers.

1. Any color described as "deep". May actually mean "very dark."
2. Any seller who does not fully answer your question. For example you ask "Does this spinel black out in sunlight?" They respond with "The spinel looks best under artificial light as most spinels do but I think you will will love this stone." If they do not answer your question then consider this a red flag.
3. "Sleepy" stones. This is usually used to describe a stone with micro inclusions that will "glow" under sunlight. However, if a stone is sleepy and not well saturated it may be a lackluster stone in sunlight. Ask for photos under multiple lighting conditions and make sure the seller has a return policy.
4. A great return policy does not mean a true representation of a stones by a vendor. For example- many pics and videos can be manipulated to show the stone at it's best. A seller can gain great feedback because they have a good return policy when the buyer is relieved that their return was accepted. If you get burned once (for example your pink or blue stone turned out to be grey) please be kind enough to give honest feedback.
 

AandCGemTradingCorp

Rough_Rock
Trade
Joined
Mar 5, 2016
Messages
10
Wow! Being new to this forum, I found this to be the most complete and sage advice that anyone could read! I would only add one more piece of advice, to trust your own instinct- both about what you are looking at and who you are dealing with- your instincts, combined with this wonderful advice, should bring you to happy conclusions in a most difficult arena!
 

Nicolette

Rough_Rock
Joined
Mar 29, 2016
Messages
7
I'm also new. After reading the whole thread filled with great advice, I'm not sure I want to jump into 'any' stone now :read: I think I'm going to continue searching and comparing for a bit longer. Thank you.
 

chrono

Super_Ideal_Rock
Premium
Joined
Apr 22, 2004
Messages
38,364

Razz

Rough_Rock
Joined
Oct 10, 2016
Messages
47
onedrop|1337722177|3201140 said:
LD: thank you for taking the time to write up all that valuable information! I am (was) clueless about colored stones, even though I've wanted one for years, but now after reading your write-up I feel so much better about making a good choice in the future!!
Another big thank you from another newbie here. I used to shy away from purchasing colored stones, but now I feel a little more confident in taking the leap into the technicolor world. Thanks for the helpful information.
 

DeNice67

Rough_Rock
Joined
Feb 7, 2017
Messages
2
wow Thank you! So much information, I am almost overwhelmed :clap: Thank you all. Its awesome to find a place like this where we can learn before we buy. I am looking at buying a Spinel, I love them! I am learning a lot but if there are direct tips to give me before I purchase my dream stone. I would appreciate it. I am learning to look by mm size instead of ct size. Correct? They seem to be bottom heavy? I attached the color....... no one in the stores in St. Louis suggests I buy one, and I don't know why also the fact that they don't carry them anywhere in my area, means I need to order. That is scary. But I am researching my butt off. Input?

peachish_pink_med_light.png
 

DeNice67

Rough_Rock
Joined
Feb 7, 2017
Messages
2
ok I found another forum from 2012 that had a lot of answers. I searched "Spinel" and I found a lot of info. I am new here, and didn't know how to do that. You guys are probably sick of Spinel questions. :)
 

minousbijoux

Super_Ideal_Rock
Premium
Joined
Aug 5, 2010
Messages
12,804
DeNice, it would be best for you to start your own thread if you want people to see your questions and respond. :))
 

catsareawesome

Rough_Rock
Joined
Apr 4, 2017
Messages
3
Hello. New kid on the block here...thank you very much for the lovely information, I certainly learned a lot! I've always been attracted to "pretty rocks" when I was a lass, then got into jewellery making, much to the delight of my teenaged daughter. I'm learning a lot along the way and want to learn more about coloured gemstones and have so many questions, will keep reading...and learning :))
 

Gems Smith

Rough_Rock
Trade
Joined
Nov 30, 2017
Messages
1
Hello,
Great information you have shared here. Thanks for this.
 

unsettled

Shiny_Rock
Premium
Joined
Jan 6, 2015
Messages
384
What great (albeit overwhelming) information!
 

Saleh001

Rough_Rock
Joined
Mar 10, 2020
Messages
9
Do fake/synthetic/man made colored gemstones have any value at all? I mean is there expensive man made colored gemstone
 

T L

Super_Ideal_Rock
Premium
Joined
Sep 20, 2008
Messages
25,159
Do fake/synthetic/man made colored gemstones have any value at all? I mean is there expensive man made colored gemstone

Not on the secondary market. In fact, the synthetic diamond market has probably trashed the value of real diamonds on the secondary market, unless they’re larger and come with a GIA report. You will never get your original purchase price for a lab stone, unless you paid very little for it in the first place.

Synthetic diamond is probably the most expensive man-made stone, especially in fancy colors.
 

TechieTechie

Shiny_Rock
Joined
Nov 8, 2014
Messages
173
Thank you for this post. Makes me breathe a bit easier if/when I sashay into the colored gem world :)
 

matt_k

Shiny_Rock
Joined
Jan 1, 2020
Messages
356
The following came about from the following thread by Roger Dery with regards to what types of stones are best suited for rings.
[URL='https://www.pricescope.com/community/threads/lowest-mohs-hardness-for-rings-other-decisive-factors.176872/#post-3220969#p3220969']https://www.pricescope.com/community/threads/lowest-mohs-hardness-for-rings-other-decisive-factors.176872/#post-3220969#p3220969[/URL]

Mohs 9 - Ruby and Sapphire: generally considered the most durable of the colored gems. If untreated in any way, will hold up very well in most all situations. Even those subjected to 'high-heat-only' still do very well. Example: my wife's 2ct oval Sapphire engagement ring was worn daily for 15 years before needing a very minor tune-up. Exception: Ruby that has been filled with substances such as glass have a much lower resistance to damage such as abrasion from wear. Ruby, under high-heat-only with flux present, will also handle wear well.

Mohs 8-1/2 - Chrysoberyl including Alexandrite: in my experience Chrysoberyl holds up very well against wear. It does not exhibit severe brittleness seen in other gems - and would be a great stone for regular wear as a ring stone.

Mohs 8 - Spinel: is generally considered a gem that wears well. It is resistant to damage and not just damage from abrasion.

Mohs 8 - Topaz: can be worn in rings, but some caution should be exhibited. This is especially true with Topaz colored blue because it has been irradiated [and then subsequently heated]. This process has weakened the stone in some way that it does not hold up as well as Precious Topaz - which may, or may not have been treated at all.

Mohs 7-1/2-8 - the Beryl family including Aquamarine, Heliodore (golden Beryl), Morganite, Goshenite wear fairly well and unless totally exposed from the metal, can be worn in rings though may not be suitable for 'everyday wear'. The heating of any of the Beryl's is done at a low temperature and it is not a factor regarding their durability. Beryl's do have an element of brittleness though not as severe as some other gems.

Mohs 7-1/2-8 - Emerald (of the Beryl family) is not well suited for everyday wear. A totally clean Emerald will hold up as well as an Aquamarine. But, finding an Emerald with that level of clarity is extremely rare. Roughly 99% of all Emeralds have been treated with a filler of some type to (usually) improve their clarity. The filler is likely to not hold up well over time. *Emerald's that have been treated should not be placed into an Ultrasonic cleaner, nor placed under a steam cleaner as this may affect the clarity enhancement substance. **Caveat: Emerald's treated with a specialized process known as "Excell" in the trade are known to have a higher level of durability over those treated with other methods.

Mohs 7-1/2 - Andalusite has reasonable wearability though it does have a slight brittleness. Facet junctions are likely to show wear after only a few years regular wear. Distinct cleavage is present in Andalusite though I have yet to see the affects of it.

Mohs 7-1/2 - Iolite in my experience holds up fairly well for hardness 7-1/2. It does, however, have distinct cleavage and a sharp blow in one or more specific directions may cause it to separate into more than one piece. Though, when I have tried to do this in the rough, I have not been successful.

Mohs 7-7-1/2 - The Garnet group is generally thought of as reasonably durable. Facet junctions will show wear within the first few years of being worn. And, the facet junctions may not chip as much as 'crumble' for lack of a better way to describe this. Of the Garnets, the Andradite/Demantoid type is the least durable, and we have found the Pyrope/Almandine/Spessartite group seem to wear slightly better.

Mohs 7-7-1/2 - The Tourmaline group is suitable for rings, though not for everyday wear especially if the top of the stone is exposed. Tourmaline can be brittle, does not hold up well where temperature changes are radical. They are known to 'chippy' as can be seen along facet junctions that are exposed.

Mohs 6-1/2 to 7-1/2 - Zircon is often thought of as brittle. Zircons heated to high temperatures (over 1,000*C) to convert them to blue are definitely more brittle and show the effects of wear easily. Blue Zircon worn high on a mounting will need refurbishing regularly. Unheated Zircons and those subjected to much lower temperatures (of various colors) are less prone to show wear - and appear less brittle. There is no known dilemma with faceting or polishing Zircon for the experienced lapidary. There is, however, a known direction to its hardness which could create difficulty for some.

Mohs 7 - The Quartz family is well known due to being available and popular. Its wear pattern is predictable. Facet junctions (even when faceting) can be 'chippy'. Chipping along the crown facets is common, and abrasions from wear are as well.

*as a general rule, at least from me, I don't suggest wearing hardness less than 7 on a regular basis as the wear will become evident well before you expect it. I do suggest moving this type of gemstone into mountings offering great protection or off the fingers or wrist.

Mohs 6-1/2 to 7 - Kunzite is not a durable gemstone. It is brittle, does not resist scratching well, does not repair easily, and has perfect cleavage in two directions. In addition to all that, it has the unfortunate problem of being light sensitive - reducing its depth of color with prolonged exposure to direct sunlight. I have repaired my fair share of Kunzite's and I don't relish the fact that they show up waiting for my handy work. But since they don't wear well over time, they will all eventually need reconditioning.

Mohs 6-1/2 to 7 - Peridot does not share the fate of Kunzite, though its wear pattern is predictable. Abrasions are readily seen on exposed gems that are frequently worn - and fortunately, a refurbishing is not usually problematic.

Mohs 6-1/2 to 7 - Tanzanite is very popular and goldsmiths have taken to mounting them in lavish and risky ways. Exposed surfaces will show wear in a relatively short time and the perfect cleavage can be a problem. Tanzanite is also heat sensitive - even though it is well known to have been heated to acquire the beautiful blue to purple hues. It is the shock of rapid temperature change that may cause damage. This is not a common situation with consumers as this is more likely to take placec in the creation or repair to a mounting.

Mohs lower than 6-1/2 - Apatite, Opal, Orthoclase/Sunstone, Scapolite, Sphene and Sphalerite and other low hardness gems all need special care to be worn in rings. It is generally accepted that these gems are best suited for pendants, pins, brooches or earrings.

Great post! So informative. I'm a newbie when it comes to colored gemstones, but I'm finding it really exciting(and sooooo much cheaper than diamonds--- especially when set in silver).

As far as the MOH scale, would you consider a Cabochon cushion cut apple green chalcedony to be suitable in toughness to wear often? And are they generally frowned upon when they have been dyed? I love the way they look, and I just pulled the trigger on a cabochon cushion cut chalcedony (it faces up kinda like a three and a half carat) in a petite 14k yellow gold setting with tiny diamond sidestones. It was 50% off for mother's day, so even if the color saturation isn't up to snuff for most colored gemstone purists, I still consider it a very pretty piece for only $290. ❤️ 67985_main.jpeg 67985_main.jpeg 67985_profile.jpeg
 

minousbijoux

Super_Ideal_Rock
Premium
Joined
Aug 5, 2010
Messages
12,804
@matt_k please start a new thread if you have questions and want the advice of other PSers.
 
Be a part of the community Get 3 HCA Results
Top