1 Definition
1.1 Definition
Troctolite is a mafic intrusive rock type. It consists essentially of major but variable amounts of olivine and calcic plagioclase along with minor pyroxene. It is an olivine-rich anorthosite, or a pyroxene-depleted relative of gabbro
Anthracite is a type of sedimentary rock which is hard and is variety of coal that has high luster
1.2 History
1.2.1 Origin
Unknown
Pennsylvania, U.S.
1.2.2 Discoverer
Christian Leopold von Buch
Unknown
1.3 Etymology
From German Troklotit, from Greek trōktēs, a marine fish (taken to be trout)
From Greek anthrakites, from anthrax, anthrak meaning coal
1.4 Class
Igneous Rocks
Metamorphic Rocks
1.4.1 Sub-Class
Durable Rock, Hard Rock
Durable Rock, Soft Rock
1.5 Family
1.5.1 Group
1.6 Other Categories
Coarse Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock