Definition
It is a metamorphic magnesium rich rock because it is composed of the mineral talc
Pegmatite rock is a holocrystalline, intrusive igneous rock which is composed of interlocking phaneritic crystals
History
Origin
USA
-
Discoverer
Unknown
R. J. Hauy
Etymology
From 17th century, because of its greasy feel and use like a soap
From Greek pegma, pegmat which means- thing joined together + -ite
Class
Metamorphic Rocks
Igneous Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Hard Rock
Family
Group
-
Plutonic
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock