Definition
Origin
Discoverer
Etymology
Class
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Group
Other Categories
Chalk is a soft, white, powdery limestone consisting mainly of fossil shells of foraminifers
From old English cealc chalk, lime, plaster; pebble, from Greek khalix small pebble, in English transferred to the opaque, white, soft limestone
Fine Grained Rock, Opaque Rock
Dunite is a green to brownish coarse-grained igneous rock mainly consisting of olivine
Ferdinand von Hochstetter
From the name of Dun Mountain, New Zealand, + -ite1
Durable Rock, Medium Hardness Rock
Coarse Grained Rock, Opaque Rock