In the gemstone world, clarity generally refers to inclusions or other impurities in a stone, and inclusions are normally counted as a bad thing. Gems are supposed to be pure as snowflakes and normally the price goes down considerably with eye-visible inclusions. In some sense, it’s similar to color grading in diamonds where the least color is generally counted as better and therefore commands a higher price. Up to a point. When the color arrives at a certain saturation a stone becomes ‘fancy’, and fancy colored diamonds can be among the most expensive in the world. Fancy clarity doesn’t really have an equivalent, but one curious exception to this is demantoid garnets.
The traditional source for Demantoid garnets is in Russia and they’ve been popular there for a hundred years because of their color and that Russian origin. The Tsars liked it. The Russian crown jewels include quite a few. Faberge liked to work with them. Like alexandrite, demantoid became a Russian cultural thing because they’re so unusual and the material is so distinctive. By the late 1980s, the site was mostly mined out and the high prices just increased the demand.
They got very expensive.
Then in 1996 demantoid was discovered in Namibia, including some big good ones coming from the Green Dragon mine. They’re a lot less money, but instead of crashing the market for the Russian material, it just divided. Big clean Green Dragon stones are quite a bit cheaper than smaller more included Russian ones. One of the distinctive things about the Russian material is the inclusions they call ‘horsetails’. These are asbestos-like inclusions of chrysotile that only appear in the Russian material. Even with microscopic inclusions that can’t be seen with the naked eye, horsetails will double or more the prices because of the Russian origin. Who knew? These aren’t graded as fancy clarity per se, but they drive up the price steeply nonetheless because they’re evidence of Russian origin and they are among the top value characteristics of this stone.