Definition
Chalk is a soft, white, powdery limestone consisting mainly of fossil shells of foraminifers
Dunite is a green to brownish coarse-grained igneous rock mainly consisting of olivine
History
Origin
-
New Zealand
Discoverer
Unknown
Ferdinand von Hochstetter
Etymology
From old English cealc chalk, lime, plaster; pebble, from Greek khalix small pebble, in English transferred to the opaque, white, soft limestone
From the name of Dun Mountain, New Zealand, + -ite1
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