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Diamond Weight  Estimator

View a short video of the Diamond Weight Estimator.

To open the Diamond Weight Estimator, click the mouse on the first scale icon on the Speed Button bar.  Select your diamond shape and press (Enter) to move to the Large Diameter box.  Using millimeters, the industry standard, enter the largest diameter or length of the diamond.  Press (Enter) to move to the next data box.  Repeat until you have filled in the data for large and small diameter, and depth.  Change the girdle thickness if necessary, and make any Weight Corrections (see below for an explanation of Corrections) which may be needed.

Tip: The list in the Shape: drop-down box have been entered in the approximate order of commonality. The shapes you are most likely to use are near the top of the list. For this reason it can be a little hard to see the shape you want. Here is how to make it easy: Just repeatedly type the first letter of the shape you are looking for. Example: press the letter O four times slowly. You will see Oval Brilliant, Old European Cut, Old Mine Cut and, finally, you'll come back to Oval Brilliant. Type the first letter of any shape you want. If you don't see it, press the letter again.

Dia Wt Est

Note: After many requests we’ve added an automatic Depth estimation (average diameter or width X .60). This was done because many diamonds are set so that it is often impossible to get an accurate depth measurement. Here the program calculates a depth based on 60% and enters it automatically (3.92 mm's).  If you have an accurate depth measurement (or would rather put in a different estimate) simply enter your data and continue on.

New in GT Pro version 6.7.0 was the information window at the bottom. Here you see what weight corrections you might need to make as well as the general formula GT Pro will use for your estimation. You can follow along with a calculator on most stones as long as the girdle is medium or less and there isn't a length-to-width ratio factor involved.

 Press F2 or select the Weight button with the mouse.  This will show the Output screen which will display the results.  See the Weight Estimation Information chart on the Info Menu for a more detailed explanation of the Corrections field.

Dia Wt Est Output

In the above example, the first four fields show the data you entered. GT Pro will also show you the Depth %, Correction Factor used and (if a shape other than round) the Length-to-width ratio. And, of course, the estimated weight is shown in the weight bar.

Corrections: Most of the time Weight Correction Factors aren't necessary. But sometimes variations in cutting can require extra corrections not accounted  for by the formulas in the Diamond Weight Estimator.

To add or subtract a percentage of weight from a diamond formula you only need to enter an integer representing the percentage in the Corrections field.

The corners on an Emerald Cut diamond are very wide, requiring a negative correction of -5%. Enter the length, width, depth, and girdle thickness. In the Corrections field enter the number -5 (with the minus sign). This will subtract 5% from the estimated weight of the diamond. To add 5% to the estimated weight simply enter 5 in the corrections field.

                          DIAMOND CORRECTIONS

  Pear:        +1 to + 5% - Squarish or high shoulders.
  Pear:        +1 to + 5% - Wide or fat wings.
  Oval:        +1 to +10% - Squarish or high shoulders.
  Marquise:    +1 to +10% - Wide or fat wings.
  Emerald Cut: +1 to +15% - Pavilion bulge.
  Emerald Cut: -1 to - 5% - Wide corners require a negative correction.

Insert: If you want to print a list of weight estimations you must manually enter each one.  This is done by pressing the Insert button on the Output Screen.  If the Print List is empty the View and Print buttons on the Output Screen will be disabled.  Once you Insert an estimation into the Print List you can look at it by pressing the View button.  You can print from the Output Screen by pressing the Print button.

PRINTING: If you want to print a report click the Print button.  If you want to add a header to print on every report select File and then Print Header.  If you don't want a header but your pages are printing too high (overwriting your existing letterhead) then increase the number in the Blank Lines box of the Print Header menu and click the Clear button.

See also Print Header

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