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
Coal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers called coal beds
1.2 History
1.2.1 Origin
1.2.2 Discoverer
Christian Leopold von Buch
John Peter Salley
1.3 Etymology
From German Troklotit, from Greek trōktēs, a marine fish (taken to be trout)
From the Old English term col, which has meant mineral of fossilized carbon since the 13th century
1.4 Class
Igneous Rocks
Sedimentary 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