Definition
Gritstone or grit is a hard, coarse-grained, siliceous sandstone
Peridotite is a dense, coarse-grained plutonic is the main constituent of the earth's mantle
History
Origin
Pennines, England
Pike County, U.S
Discoverer
J.J. Ferber
Unknown
Etymology
From Grit + Stone
From French, from peridot + -ite
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Family
Group
-
Plutonic
Other Categories
Coarse Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock