Diamond Jewelry Forums

Picture Gallery

Video Gallery

|

Search |

Posted Today |

Most Active |

Help

ť Home ť

ť Diamond Prices and Grading ť

ť RockyTalky ť

ť Convert percentages to angles???

Convert percentages to angles???

P: 4/24/2003 5:16:07 PM
hunter3316 Rough Rock Total Posts: 30 Last Post: 8/27/2003 Member Since: 4/1/2003	Can anyone tell me how to convert crown and pav. percentages to angles... assuming no cullet. I want to do it for these two diamonds: 1: Depth:61.3% Table; 56% Crown: 14% Pavilian: 43% 2: Depth:59.9% Table;58% Crown:14% Pavilian:43% thanks for your great help!!!! NOne
Posted: 4/24/2003 5:16:07 PM

There are 7 replies to this message. There are 7 replies on this page.

P: 4/24/2003 5:32:02 PM
Pricescope Administrator Total Posts: 8,265 Last Post: 1/5/2008 Member Since: 1/1/2000	Did you get the data from EGL report? If they are rounded there will be rather high error in HCA. You can use these formulas to convert % to angles without culet: CrownAngle = ATAN (2 * CrownDepth% / (100 - TableSize)) PavilionAngle = ATAN (PavilionDepth% / 50) Pricescope
Posted: 4/24/2003 5:32:02 PM

P: 4/24/2003 5:47:32 PM
MikeC Rough Rock Total Posts: 17 Last Post: 4/25/2003 Member Since: 4/3/2003	---------------- On 4/24/2003 5:322 PM leonid wrote: Did you get the data from EGL report? If they are rounded there will be rather high error in HCA. You can use these formulas to convert % to angles without culet: CrownAngle = ATAN (2 * CrownDepth% / (100 - TableSize)) PavilionAngle = ATAN (PavilionDepth% / 50) ---------------- I was wondering how to do this as well. leonid, Thanks for the equation, but what does ATAN stand for? Mike
Posted: 4/24/2003 5:47:32 PM

P: 4/24/2003 5:58:40 PM
Pricescope Administrator Total Posts: 8,265 Last Post: 1/5/2008 Member Since: 1/1/2000	---------------- ... but what does ATAN stand for? Mike ---------------- Mike, ATAN (Arctangent) is reciprocal to TAN (Tangent) On Windows' Calculator (Scientific Mode) select INV and hit TAN. Pricescope
Posted: 4/24/2003 5:58:40 PM

P: 4/24/2003 6:03:34 PM
hunter3316 Rough Rock Total Posts: 30 Last Post: 8/27/2003 Member Since: 4/1/2003	Thanks, thats exactly what I was lookin for. To answer your question YES, these numbers are from EGL. How much of an eror could I expect, according HIC scoring. I supose theres no other way to fix this except to do the SERIN hu? Also whats the average error for converting EGL %'s to HIC scores? Thanks! NOne
Posted: 4/24/2003 6:03:34 PM

P: 4/24/2003 6:15:04 PM
MikeC Rough Rock Total Posts: 17 Last Post: 4/25/2003 Member Since: 4/3/2003	Thanks leonid. Originally I just had the pav. percentage and got a score of 1 on the HCA but was not to sure how reliable that was because it was a percentage and not an angle. After doing the conversion my score actually went down to .9. That made my day
Posted: 4/24/2003 6:15:04 PM

P: 4/24/2003 8:48:42 PM
Pricescope Administrator Total Posts: 8,265 Last Post: 1/5/2008 Member Since: 1/1/2000	hunter3316: ---------------- I supose theres no other way to fix this except to do the SERIN hu? ---------------- Correct... ---------------- Also whats the average error for converting EGL %'s to HIC scores? ---------------- It depends on particular values. I just tried to plug pavilion depth of 43.0% and 43.5%. In both cases I've got HCA < 2 which is pretty good. However, there will be more dramatic difference once you go closer to 43.8%-44.0% pavilion depth since diamond will leak more light under the table. Pricescope
Posted: 4/24/2003 8:48:42 PM

P: 4/24/2003 8:56:25 PM
Pricescope Administrator Total Posts: 8,265 Last Post: 1/5/2008 Member Since: 1/1/2000	Mike, actually when one enters pavilion or crown depth %, HCA converts it into angles anyway because HCA is based on angles. We believe Sarin angle data are more accurate than depth% because later depends on accuracy of girdle and culet measurements. Still, even angles data have certain error so don't fight for each tenth of HCA score Pricescope
Posted: 4/24/2003 8:56:25 PM

Previous Page

Next Page

Ť Diamond mixup--wrong cert Ť

ť Diamond buying experience - GoodOldGold ť

Next Topics
Are these good deals? Is Hyde Park (Denver/LasVegas/Aspen) a good jeweler? Opinions Needed! Another World's Ugliest Diamonds Post large stones Leonid Local Jewelry Store Experience Advice needed on a stone sources for small marquise stones Does anyone recognize this setting? Princess girdle, and other setting questions H&A listed on a report? resizing a Vatche? What does it take to become a gemologist???? Did I get a good deal on this ring? Worried about reliability of E-Diamond... TIFFANY 6 PRONG SOLITAIRE Is Insurance Recommended & How? Blue Nile settings Arizona Questions for the Professionals Custom Setting? Rhino Check your PM! Thanks! nm Question about yellow diamonds Please review my purchase. What Do You Think of This? Warped?! (And Why Does GIA & Sarin Differ?) Engagement Ring - Local/Online? - Cut Advisor??? Direct light and dim light, and cut and brilliancescope? Is A.I.G. a reliable lab? USA Certed Diamonds kicks butt! Appraisers in Los Angeles to validate ideal cut/H&A Pictures of 2.5ct round in Royal Crown setting ?

Jump to:

Contact Us \| Back Home \| Privacy Statement \| Forum Agreement \| Forum Policies
Ideal BB Version: 0.1.5.4.beta1	Message forum software powered by the Ideal BB

Pricescope - Knowledge - Diamond Prices - Tools - Resources - About

Š 2000-2009 Pricescope. Terms of Use Privacy Policy Disclaimer
forum archives