This is another of the rock types recently discovered. It was first described in the 1940's but didn't become popular until 1978. It, like lapis lazuli, is valued because of it's beautiful color. I've got two examples - one w/ the typical swirling pattern and one w/ a pearl-like luster. It's hardness is 4.5 to 5. Charoite was created by limestone undergoing contact metamorphism (transformation through heat, pressure, and infusion of other chemicals). While that process is a common geological phenomena, whatever occurred to specifically make charoite happened in only one location - Siberia, Russia near the Chary river. Another reason this rock is highly prized - there is a limited supply that could eventually be mined out.