Charoite
Charoite has only recently come on the market. It was discovered in Siberia, Russia in 1947, but only became known internationally in 1978. Most believe the stone was named for the nearby Chara River.
Charoite has a lovely dark purple color with a swirling, fibrous appearance, and is sometimes chatoyant. The material is a silicate of potassium, calcium and sodium.
Chemistry: (Ca,K,Na)3Si4O10(OH,F)H2O ♦ Crystal system: Monoclinic - prismatic ♦ Crystal habit: Fibrous, massive ♦ Transparency: Translucent ♦ Play of color: Chatoyant ♦ Color: Violet, lilac, light brown ♦ Luster: vitreous to pearly ♦ Moh's hardness: 5 - 6 ♦ Localities: Siberia, Russia