Definition
Coal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers called coal beds
Borolanite is a variety of Nepheline Syenite and belongs to igneous rocks and contains nepheline-alkali feldspar pseudomorphs which occur as conspicuous white spots in the dark rock matrix
History
Origin
USA
Scotland
Discoverer
John Peter Salley
Unknown
Etymology
From the Old English term col, which has meant mineral of fossilized carbon since the 13th century
From Alkalic Igneous complex near Loch Borralan in northwest Scotland
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Medium Hardness Rock
Family
Group
-
Plutonic
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock