Definition
Tonalite is a coarse-grained plutonic rock consisting mainly of sodic plagioclase, quartz, and hornblende or other mafic minerals with phaneritic texture
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
History
Origin
Tonale, Italy
-
Discoverer
Warren Hamilton
Christian Leopold von Buch
Etymology
From Tonale Pass, northern Italy, + -ite1
From German Troklotit, from Greek trōktēs, a marine fish (taken to be trout)
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Family
Group
Plutonic
Plutonic
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock