Education

Girdle Thickness Effect (11.08)

With an averaged medium girdle no girdle thickness adjustment, (GTA), is required. If thicker a percentage will be added and if thinner a percentage will be deducted in the weight...

Judgment of Girdle Thickness (11.09)

With a range of girdle thicknesses take an average to use in the girdle thickness adjustment formula, (GTA).

The Conservative Approach (11.10)

When making an offer on a diamond be conservative on the grading and weight estimate, (assuming there is no documentation to back it up).

Round Brilliant Weight Estimation (11.11)

The very common round brilliant diamond weight estimate formula.

Fancy Shape Weight Estimation Introduction (11.12)

Prongs over marquise ends or a pear shape end makes it more challenging to measure lengths to plug into weight estimated formula.

Additional Adjustments (11.13)

Add additional weight estimate adjustments for other proportion characteristics beyond the girdle thickness adjustment.