Definition
Dacite is a volcanic igneous rock which is rintermediate in composition between andesite and rhyolite
Tonalite is a coarse-grained plutonic rock consisting mainly of sodic plagioclase, quartz, and hornblende or other mafic minerals with phaneritic texture
History
Origin
Romania and Moldova, Europe
Tonale, Italy
Discoverer
Unknown
Warren Hamilton
Etymology
From Dacia, a province of the Roman Empire which lay between the Danube River and Carpathian Mountains where the rock was first described
From Tonale Pass, northern Italy, + -ite1
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Hard Rock
Family
Group
Volcanic
Plutonic
Other Categories
Fine Grained Rock, Medium Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock