Definition
Claystone is a fine-grained, dark gray to pink sedimentary rock which mainly consists of compacted and hardened clay
Lignite is a soft brownish coal which shows traces of plants and is intermediate between bituminous coal and peat
History
Origin
-
France
Discoverer
Unknown
Unknown
Etymology
From English clay and stone as the rock contains more amount of clay
From French, Latin lignum wood + -ite1
Class
Sedimentary Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Medium Hardness 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