Definition
Lignite is a soft brownish coal which shows traces of plants and is intermediate between bituminous coal and peat
Rapakivi Granite is a hornblende-biotite Granite containing large rounded crystals of orthoclase which are mantled with oligoclase
History
Origin
France
Finland, Europe
Discoverer
Unknown
Jakob Sederholm
Etymology
From French, Latin lignum wood + -ite1
From Finnish Rapakivi which stands for crumbly rock
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Hard Rock
Family
Group
-
Plutonic
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock