Noun
A silicate of aluminium, occurring usually in thick rhombic prisms, nearly square, of a grayish or pale reddish tint. It was first discovered in Andalusia, Spain.
Source: Webster's dictionaryA subgroup is the andalusite -, staurolite -, kyanite - and sillimanite -schists which usually make their appearance in the vicinity of gneissose granites, and have presumably been affected by contact metamorphism. Source: Internet
Kyanite is triclinic, while andalusite and sillimanite are both orthorhombic and belong to the dipyramidal point group. Source: Internet