Definition
Pumice is a volcanic rock that consists of highly vesicular rough textured volcanic glass, which may or may not contain crystals
Rhyolite is a fine-grained igneous rock which is rich in silica
History
Origin
Spain
North America
Discoverer
Unknown
Ferdinand von Richthofen
Etymology
From Old French pomis, from a Latin dialect variant of pumex
From German Rhyolit, from Greek rhuax lava stream + lithos stone
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Family
Group
Volcanic
Volcanic
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock