Definition
Rhyolite is a fine-grained igneous rock which is rich in silica
Migmatite is typically a granitic rock within a metamorphic host rock which is composed of two intermingled but distinguishable components
History
Origin
North America
Southern Alps, France
Discoverer
Ferdinand von Richthofen
Jakob Sederholm
Etymology
From German Rhyolit, from Greek rhuax lava stream + lithos stone
From the Greek word migma which means a mixture
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Family
Group
Volcanic
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Other Categories
Coarse Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock