Definition
Chalk is a soft, white, powdery limestone consisting mainly of fossil shells of foraminifers
Peridotite is a dense, coarse-grained plutonic is the main constituent of the earth's mantle
History
Origin
-
Pike County, U.S
Discoverer
Unknown
Unknown
Etymology
From old English cealc chalk, lime, plaster; pebble, from Greek khalix small pebble, in English transferred to the opaque, white, soft limestone
From French, from peridot + -ite
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Medium Hardness Rock
Family
Group
-
Plutonic
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock