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Idaho Star Garnet

Rock&Gem Magazine

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June 2021

Brilliant colors enhance the beauty and add to the value of many of our gemstones, especially those that are clear or translucent. And I like any color… as long as it is red. For that reason, the blood-red ruby is about my favorite gemstone. And in museums around this country and in Europe I have seen carefully cut cabochons containing startling six-rayed stars that seem to slide over the surface of the stone as it is rotated in the light. It is no wonder that, for hundreds of years, the star ruby has been one of the favorite stones of royalty.

- Earl Spendlove

Idaho Star Garnet

Editor’s Note: This article originally appeared in the February 1985 issue of Rock & Gem, written by Earl Spendlove.

Unfortunately, I couldn’t buy a star ruby, even if I mortgaged my mother-in-law’s false teeth. Then, a couple of years ago Phil Andrist, a dealer at a rock show, from Bandon, Oregon showed me some beautiful, translucent, burgundy red, almandine garnet cabochons that contained some very nice four- and six-rayed stars.

The material had come from the Emerald Creek area in northern Idaho, and he said he had collected it himself. He had both finished cabochons and rough material and, since I like do things myself, I bought some of the rough. Then, following Phil’s directions, I made a couple of cabochons and was really pleased with the results.

As far as we know, star garnets are found only in northern Idaho and in India. The effect is called “asterism,” meaning star-like. Six-rayed stars are found in garnet, ruby, sapphire, and certain quartz stones, but only garnet has both four- and six-rayed stars. The phenomenon results from light reflected from rutile needles, or crystals, aligned in a certain pattern. Garnet stars can best be seen when the stone is cut as a cabochon and viewed in the sunlight, under a bare bulb, or in the beam of a sharply focused flashlight.

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