Definition
Appinite is an igneous rock in which the crystals are so fine grained that individual minerals cannot be easily distinguished
Anthracite is a type of sedimentary rock which is hard and is variety of coal that has high luster
History
Origin
-
Pennsylvania, U.S.
Discoverer
Unknown
Unknown
Etymology
From the variety of Lamprophyre Greek lampros bright and shining + porphureos purple
From Greek anthrakites, from anthrax, anthrak meaning coal
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Soft Rock
Family
Group
Plutonic
-
Other Categories
Coarse Grained Rock, Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock