Definition
Chert is a hard, dark, opaque sedimentary rock which is composed of silica with an amorphous fine-grained texture
Coal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers called coal beds
History
Origin
-
USA
Discoverer
Unknown
John Peter Salley
Etymology
From flint-like quartz, 1670s, of unknown origin- a local term, which has been taken into geological use
From the Old English term col, which has meant mineral of fossilized carbon since the 13th century
Class
Sedimentary Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Soft Rock
Family
Group
-
-
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock