Definition
Anthracite is a type of sedimentary rock which is hard and is variety of coal that has high luster
Andesite is a dark, fine-grained, brown or greyish intermediate volcanic rock which is a commonly found in lava
History
Origin
Pennsylvania, U.S.
North America
Discoverer
Unknown
Theodor von Gümbel
Etymology
From Greek anthrakites, from anthrax, anthrak meaning coal
From Andes mountains, where it is found in abundance
Class
Metamorphic Rocks
Igneous Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Hard Rock
Family
Group
-
Volcanic
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock