Star ANd Catseye Gems, Moonstones, Color Effects
ADDITIONAL NOTES ON STAR AND CATSEYE GEMS, MOONSTONES, ETC.
As previously explained, star- and catseye-causing inclusions, and those responsible for moonstone, sunstone, and other sheen or color effects, occur in certain planes in the host crystal. It is up to the cutter to examine the rough to determine how he can best cut it to place the special effect squarely on top where it belongs.
If the optical display does not appear on top, it will be seen well only from one side instead of from all sides, depending on how much the ideal direction is deviated from. Because of the high value of star and catseye gems of good to fine quality, native cutters, particularly in Ceylon, attempt to make each gem as large as possible, even if it means a lopsided star or eye.
These defects, and others, are shown picture. If the star or eye effect is not greatly off to one side, the gem may be purchased with a view to recutting because too much weight will not be lost. However, if the effect is greatly displaced, the gem may be a very poor investment due to the large amount of material that must be re¬moved to correct the position of the eye or star.
The tendency to cut these gems as large as possible manifests itself in another irritating trick practiced by the Ceylon cutters. This is to cut the gems into nearly spheri¬cal balls even though only the polished top half can conceivably con¬tribute to the star or eye effect. Native sellers attempt to assure the hesitant customer that the bottom bulge is needed to “reinforce” the effect; this is simply not so. However, the bottom bulge may have good star or catseye material in it; if it does, the buyer may have the sphere¬like gem cut in half and the bottom recut into another gem. Unfortu¬nately, in most instances, the lapidary has already satisfied himself that the bottom bulge is poor material whose only value is to add weight and inflate the price.