Cutting Star and Cat’s Eye Gems


Well-cut star and cat’s eye gems are a delight to the eye and great fun to cut. These phenomenal stones display asterism and chatoyancy, respectively. Both effects are the result of light reflecting off inclusions within the gemstones. Although silk (fine included crystals) is the most common cause of these visual phenomena, any inclusions that reflect light in parallel lines can create these displays, including hollow tubes, feathers, and veils.

How many times have you seen off-color, faceted sapphires caused by gold rutile inclusions clouding the interior? Many of these would have produced a nearly transparent star stone if properly oriented. The star versions are worth more and are a lot easier to sell! Here’s a secret. Many pieces of low-grade facet rough may produce fabulous star or cat’s eye gems. This is true for emerald, aquamarine, and tourmaline as well as sapphire. You just need to find stones with the right inclusions. Once you become familiar with them and start looking for their unique properties, you’ll find phenomenal stones that would otherwise be overlooked.

Once, a top collector told me he needed malaya garnet cat’s eye gems. Unfortunately, they were “practically nonexistent.” I …

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