WEIGHT ESTIMATION CORRECTION FACTORS

  Variations in cutting can require extra corrections not accounted
  for by the formulas in the Diamond Weight Estimator and the Colored
  Stone Weight Estimator.

                                           DIAMONDS

  To add or subtract a percentage of weight from a diamond formula you
  only need to enter the percent number in the Corrections field.
  Example:
  The shoulders on a pear shape diamond are very high, requiring a

  correction of +5%. Enter the length, width, depth, and girdle
  thickness. In the Corrections field enter the number 5. This will add
  5% to the estimated weight of the diamond. To remove 5% from 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.
  ______________________________________________________________ ________                    

                           COLORED STONES

  In the Colored Stone Weight Estimator we use the Bulge Factor field for
  any weight corrections that are required. Just add any additional
  correction to the bulge factor. Example: A rectangular step cut

  (emerald cut) stone has a bulge factor of +12% but very wide corners
  requiring a negative correction of -5%. Select User Defined in the
  Bulge Factor field and enter 7.
 
                     COLORED STONE CORRECTIONS

  All Shapes: +1 to +10% - High or lumpy crowns.
  Heart:     +1 to + 5% - Fat wings or wide lobes.   
  Marquise:  +1 to +10% - Wide wings.
  Marquise:  -1 to - 5% - Very straight wings (rare).
  Marquise:  -1 to - 3% - No keel line or a very short keel line.

  Oval:      +1 to +10% - Squarish or high shoulders.      
  Pear:      +1 to + 5% - Wide wings.
  Pear:      -1 to - 3% - Very straight wings (rare).
  Pear:      -1 to - 3% - No keel line or a very short keel line.
  Pear:      +1 to + 5% - Squarish or high shoulders.
  Step Cuts: +1 to + 5% - Long culet steepens pavilion angles.
  Step Cuts: +1 to +18% - Crown, or more likely, pavilion bulge.
  Step Cuts: -1 to - 5% - Wide corners require a negative correction.

  Triangular: -1 to -10% - Straight sides require a negative correction.

  Note: There are four types of cushion shapes:

         Square Antique Cushion    : Has rounded corners
         Rectangular Antique Cushion: Has rounded corners
         Square Cushion            : Has sharp corners
         Rectangular Cushion       : Has sharp corners

  Don't forget the peculiarity of measuring a square antique cushion
  shaped colored stone. The first part of the formula squares the average
  diameter. To arrive at the average diameter you measure from belly to
  belly (straight across) and from corner to corner (diagonally).