Definition
Arkose is a sedimentary rock, specifically a type of sandstone containing at least 25% feldspar
Lignite is a soft brownish coal which shows traces of plants and is intermediate between bituminous coal and peat
History
Origin
France
France
Discoverer
Alexandre Brongniart
Unknown
Etymology
From Auvergne region of France used by a French geologist Alexandre Brongniart in 1826 who applied this term to some feldspathic sandstones
From French, Latin lignum wood + -ite1
Class
Sedimentary Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Soft Rock
Family
Group
-
-
Other Categories
Coarse Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock