pegmatite

/peg-muh-tahyt/US // ˈpɛg məˌtaɪt //UK // (ˈpɛɡməˌtaɪt) //

伟晶岩,伟晶石,伟格岩,伟哥

Definitions

n.名词 noun

1
Petrology.
- : a coarsely crystalline granite or other high-silica rock occurring in veins or dikes.

Chrysoberyl is known as a constituent of certain kinds of granite, pegmatite and gneiss.
Pegmatite and Porphyry (with a very few small crystals of felspar) and Gneiss?
I observed Pegmatite of a white colour, and hornblende Porphyry and Diorite.
The hills on which I stood were composed of Pegmatite, with patches of white Mica in large leaflets.
In one of the creeks I observed pegmatite; pebbles of talc-schiste and of white quartz covered the bed of the river.