Definition
Origin
Discoverer
Etymology
Class
Sub-Class
Group
Other Categories
Rhyodacite is an extrusive volcanic rock intermediate in composition between dacite and rhyolite
Rhyo lite + dacite : a rock intermediate between rhyolite and dacite that is the extrusive equivalent of granodiorite
Durable Rock, Medium Hardness Rock
Fine Grained Rock, Opaque Rock
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
Christian Leopold von Buch
From German Troklotit, from Greek trōktēs, a marine fish (taken to be trout)
Coarse Grained Rock, Opaque Rock