Definition
Origin
Discoverer
Etymology
Class
Sub-Class
Group
Other Categories
Banded iron formation are distinctive units of sedimentary rock that are almost always of Precambrian age
Western Australia, Minnesota
From its formation process
Durable Rock, Medium Hardness Rock
Coarse Grained Rock, Opaque Rock
Lignite is a soft brownish coal which shows traces of plants and is intermediate between bituminous coal and peat
From French, Latin lignum wood + -ite1
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock