FOLDS.NET has
programs for calculating diamond proportions.
This page shows what computers can run these programs,
and how you can run the programs.
"Diamond Cross-Section" is the easiest-to-use program at FOLDS.NET. If you see a big button above this paragraph, just click on it to run the program. If you click on the button, but the program does not work, please let me know so I can fix the problem.
"Diamond Cross-Section" lets you adjust Tolkowsky's geometric model. It uses the formulas in the editor's notes of Diamond Design and the girdle article. You can choose the pavilion angle (between 39 and 42 degrees). You can choose either a knife-edge girdle (a la Tolkowsky) or a real girdle (between 0 and 3 percent at the thin parts = "scallops").
(If you want to try unusual values, please use a different program, like CrossSection.class or GirdledSection.class .)
You can choose to see just the results, or see the step-by-step calculations. Given your parameters, the program draws a custom version of Tolkowsky's Figure 35. The program calculates the crown angle and table ratio that correspond to your pavilion angle angle and girdle thickness.
"Diamond Cross-Section"
has been tested on a system with
Windows NT 4.0 and Netscape 3.01 running Java 1.02.
I expect it to work on nearly all web browsers that run Java.
The good news:
You probably don't need to run "CrossSection.class" by itself,
because it is built into "Diamond Cross-Section".
The bad news:
You might not be able to run "CrossSection.class" by itself,
because it requires a tricky computer set-up.
CrossSection.class
is the Java 2 program that calculated
the bold curves in Figure 3
of the Diamond Design summary.
You can use it to extrapolate the bold curves
-- but you may get a poor diamond (like a fish-eye or nail-head).
CrossSection.class only calculates the proportions of knife-edge diamonds.
CrossSection.class has been tested on a system with:
I expect that CrossSection.class works on other operating systems
(besides Windows NT 4.0) if all of the other requirements are met.
The good news:
You probably don't need to run "GirdledSection.class" by itself,
because it is built into "Diamond Cross-Section".
The bad news:
You might not be able to run "GirdledSection.class" by itself,
because it requires a tricky computer set-up.
GirdledSection
is the Java 2 program that calculated
the thin curves and dashed curves in Figure 3
of the Diamond Design summary.
You can use it to extrapolate these curves,
or to find curves for very thick girdles
or to find curves for negative girdle thicknesses
(partly knife-edge diamonds).
But you may get a poor diamond (like a fish-eye or nail-head).
I expect that GirdledSection.class works on other operating systems
(besides Windows NT 4.0) if all of the other requirements are met.
The good news:
If you have a Microsoft Windows computer,
you can probably run "DiamondDimension.exe" .
The bad news:
If you don't have a Microsoft Windows computer,
you probably can't run "DiamondDimension.exe" .
DiamondDimension.exe
is a Win32 console application. It is written in C++.
You can run it from a DOS prompt,
or by double-clicking it in Windows Explorer / File Manager.
DiamondDimension.exe calculates the lengths of all of the edges of a perfectly symmetrical diamond. DiamondDimension makes some assumptions (about the star facets, upper girdle facets, and lower girdle facets) that are different from Tolkowsky's recommendations.
DiamondDimension.exe has been tested on a system with:I expect that DiamondDimension.exe works on
Windows 95/98/ME and Windows NT/2000/XP,
if all of the other requirements are met.
I do not know if DiamondDimension.exe works on Windows 3.1 .
The software is copyright 2001 by Jasper Paulsen. All rights reserved. Your comments and questions are welcomed.
More acknowledgements: I thank the late Marcel Tolkowsky for writing Diamond Design. I thank everyone kind enough to criticize this web-site, and tell me things that I should fix. Many people (listed above) have provided programming suggestions and/or code snippets. Garry Holloway, Marvin Leib, Bruce Harding, Martin Haske, Jefferson Lewis, and Iiro Suokko have pointed out errors and omissions. If you notice one, please let me know, and I will do my best to fix it promptly.
DISCLAIMER: This information and software are for educational purposes only and should not be used in place of services from a professional appraiser. Formulas cannot be 100% accurate due to subtleties not included in the formulas. All decisions should be based on your own knowledge. I cannot accept any responsibility for decisions you make.
Thank you for visiting
FOLDS.NET.
This page is
copyright 2001 by
Jasper Paulsen.
Your comments are welcomed.
Last updated November 12, 2001.