NOT REQUIRED FOR STUDENTS OF GEOLOGY 306

Oval faceted stones: Diameter squared x depth x S.G. x .002 = carat wt.

Emerald cut faceted stones: Length x width x depth x S.G. x .0025 = carat wt.

Rectangular faceted stones: Length x width x depth x S.G. x .0026 = carat wt.

Square cut faceted stones: Length x width x depth x S.G. x .0023 = carat wt.

Marquise cut stones, (navette): Length x width x depth x S.G. x .0016 = carat wt.

Pear cut stones: Length x width x depth x S.G. x .00175 = carat wt.

Square cushions:(avg. corner meas.& belly meas. for dia.) Diameter squared x depth x S.G. x .0018 = carat wt.

Rectangular Cushions:(avg. L & W for dia.) Diameter squared x depth x S.G. x .0022 = carat wt.

Square step cut stones:(avg. both meas. for dia.) Diameter squared x depth x S.G. x .0023 = carat wt.

Rectangular step cut stones: Length x width x depth x S.G. x .0025 = carat wt.

Cabochon cut stones: Length x width x depth x S.G. x .0027 = carat wt.