Definition
Chalk is a soft, white, powdery limestone consisting mainly of fossil shells of foraminifers
Jasperoid is a rare, peculiar type of metasomatic alteration of rocks
History
Origin
-
USA
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 silica, the main mineral content of Jasperoid
Class
Sedimentary Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Medium Hardness Rock
Family
Group
-
-
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock