Triphane
Triphane is a mineral belonging to the borate group. It is also known by the mineralogical name rhodizite. Triphane has the chemical formula (K,Cs)Al4B11O20(OH) or (K,Cs)Be3Al6B12O27(OH)2. The presence of cesium (Cs) can be significant, sometimes making up a notable portion of the alkali metal content. It is a rare mineral, typically found in lithium-rich pegmatites. Crystals of triphane are usually small and can occur as prismatic or acicular aggregates. The color of triphane is typically colorless, white, or pale yellow. It is transparent to translucent. The hardness of triphane on the Mohs scale is around 6.5 to 7. Its specific gravity is approximately 3.5. Triphane was first described in 1834 from a find in the Ural Mountains of Russia. Other notable occurrences include Greenland, Madagascar, and the United States. Due to its rarity and small crystal size, triphane is not a commercially important mineral, but it is of interest to mineral collectors and geologists for its unique chemical composition and occurrence in specific geological environments.