Definition
Variolites are a group of dark green basic igneous rocks which exhibit pale colored spots, or spherules, especially on weathered surfaces, that give them a pockmarked appearance
Arkose is a sedimentary rock, specifically a type of sandstone containing at least 25% feldspar
History
Origin
France
France
Discoverer
Unknown
Alexandre Brongniart
Etymology
From Latin varius, speckled, variegated
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, Hard Rock
Durable Rock, Hard Rock
Family
Group
Volcanic
-
Other Categories
Opaque Rock
Coarse Grained Rock, Opaque Rock