gowanite

Gowanite is a rare mineral with the chemical formula (Ca,Na)2(Fe,Mn)3+Si8O20(OH)2. It was first discovered in 1969 in the Gowanda mine, New York, USA, and is named after the mine. Gowanite is typically found in metamorphic rocks, particularly in contact metamorphic zones around granitic intrusions. It is often associated with minerals such as garnet, epidote, and actinolite.

Gowanite crystallizes in the monoclinic system and typically forms prismatic crystals. It is usually found in shades of brown, green, or black, depending on the presence of iron and manganese. The mineral has a hardness of approximately 6.5 on the Mohs scale and a specific gravity of around 3.2 to 3.3.

The structure of gowanite is complex, featuring a framework of silica tetrahedra and octahedrally coordinated iron and manganese. The mineral's name is derived from the Greek words "gowa" meaning "to be born" and "nite" meaning "new," reflecting its rarity and recent discovery.

Gowanite is of limited economic interest due to its rarity and the difficulty in extracting it from its host rocks. However, it is occasionally collected by mineral enthusiasts for its aesthetic appeal and scientific significance. The mineral's rarity and unique properties make it a subject of interest for geologists and mineralogists studying metamorphic processes and the formation of silicate minerals.