Definition
Coal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers called coal beds
An iron rich extrusive rock found as a member of the alkali basalt magma series
History
Origin
USA
Isle of Mull, Scotland
Discoverer
John Peter Salley
Ben More
Etymology
From the Old English term col, which has meant mineral of fossilized carbon since the 13th century
From the name of discoverer, Ben More
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Medium Hardness Rock
Family
Group
-
Volcanic
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock