Definition
It is a metamorphic magnesium rich rock because it is composed of the mineral talc
Rhyodacite is an extrusive volcanic rock intermediate in composition between dacite and rhyolite
History
Origin
USA
USA
Discoverer
Unknown
Unknown
Etymology
From 17th century, because of its greasy feel and use like a soap
Rhyo lite + dacite : a rock intermediate between rhyolite and dacite that is the extrusive equivalent of granodiorite
Class
Metamorphic Rocks
Igneous Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Medium Hardness Rock
Family
Group
-
Volcanic
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock