Definition
Lignite is a soft brownish coal which shows traces of plants and is intermediate between bituminous coal and peat
Phonolite is an uncommon extrusive igneous rock volcanic rock of intermediate chemical composition between felsic and mafic
History
Origin
France
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Discoverer
Unknown
Unknown
Etymology
From French, Latin lignum wood + -ite1
From the Greek meaning sounding stone because of the metallic sound it produces if an unfractured plate is hit
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Medium Hardness Rock
Family
Group
-
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Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock