Definition
Gabbro is an intrusive igneous rock which is chemically equivalent to plutonic Basalt
Trachyte is a grey fine-grained volcanic rock which mainly consists of alkali feldspar
History
Origin
Germany
-
Discoverer
Christian Leopold von Buch
Alexandre Brongniart and René Just Haüy
Etymology
From Latin glaber bare, smooth, bald
From Greek trakhus rough’ or trakhutēs roughness
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Family
Group
Plutonic
Volcanic
Other Categories
Coarse Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock