Definition
Andesite is a dark, fine-grained, brown or greyish intermediate volcanic rock which is a commonly found in lava
Gritstone or grit is a hard, coarse-grained, siliceous sandstone
History
Origin
North America
Pennines, England
Discoverer
Theodor von Gümbel
J.J. Ferber
Etymology
From Andes mountains, where it is found in abundance
From Grit + Stone
Class
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Family
Group
Volcanic
-
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock