Definition
Rhyolite is a fine-grained igneous rock which is rich in silica
Basalt is a common extrusive igneous rock formed by the rapid cooling of basaltic lava exposed at or very near the surface of Earth
History
Origin
North America
Egypt
Discoverer
Ferdinand von Richthofen
Georgius Agricola
Etymology
From German Rhyolit, from Greek rhuax lava stream + lithos stone
From Late Latin Basaltes (variant of basanites ), very hard stone, which was imported from Ancient Greek Basanites
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Family
Group
Volcanic
Volcanic
Other Categories
Coarse Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock