sillimanite
Noun
Meaning
Same as Fibrolite.
Source: Webster's dictionarySynonyms
Hypernyms
Examples
A 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.
Kyanite is triclinic, while andalusite and sillimanite are both orthorhombic and belong to the dipyramidal point group.
It consists of sillimanite K-feldspar grade schist and gneiss intruded by numerous sills and dikes of leucogranite ranging in thickness from 1 cm to 1,500 m (0.4 in to 4,900 ft).
In this example, the rock has prominent sillimanite porphyroblasts as large as convert.