Definition
Pumice is a volcanic rock that consists of highly vesicular rough textured volcanic glass, which may or may not contain crystals
Arkose is a sedimentary rock, specifically a type of sandstone containing at least 25% feldspar
History
Origin
Spain
France
Discoverer
Unknown
Alexandre Brongniart
Etymology
From Old French pomis, from a Latin dialect variant of pumex
From Auvergne region of France used by a French geologist Alexandre Brongniart in 1826 who applied this term to some feldspathic sandstones
Class
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Family
Group
Volcanic
-
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock