Description
These neptunite crystals are from the Gem Mine in the New Idria District of San Benito County, California, USA. This mine is referred to by many names but they are all the same locale in California. This mine produces the best and largest crystals for the species. Other locations contain small or microscopic crystals. It is a rare silicate that contains the elements Na, K, Li, Fe, Ti, Si and O.. The mine is no longer producing and all material available is from old stock. This specimen consists of a crossite ( sawed on backside) matrix that is mostly covered with white natrolite and dozens of black (reddish) neptunite crystals up to 23 mm long. This piece measures 6 x 4 1/2 x 2 /8 inches or 153 x 114 x 53 mm
