Mineral Species: Ferrohornblende

Chemical Formula: Ca2[(Fe2+;Mg)4Al](Si7Al)O22(OH)2

Chemical Name: Calcium Iron Magnesium Silicate Hydroxide

Mineral Class: Inosilicate

Mineral Notes:  Ferrohornblende occurs in altered granites, granodiorites, and metabasalts. It common in amphibolites and schists. The mineral a series with magnesiohornblende. Ferrohornbende is named for its ferrous iron content and from the German for 'horn' and 'to deceive', in allusion to its similarity to valuable minerals in ores.

Description: Excellent crystals of Ferrohornblende in a Quartz and Albite matrix. The grey-green crystals are thin elongated needles and on one side of the matrix they are clustered into a fan-like aggregate. Crystalline Ferrohornblende like this is very rare.

Location: Mirosov, Czech Republic.