Definition
Banded iron formation are distinctive units of sedimentary rock that are almost always of Precambrian age
Trachyte is a grey fine-grained volcanic rock which mainly consists of alkali feldspar
History
Origin
Western Australia, Minnesota
-
Discoverer
Johann Gottlob Lehmann
Alexandre Brongniart and René Just Haüy
Etymology
From its formation process
From Greek trakhus rough’ or trakhutēs roughness
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
Family
Group
-
Volcanic
Other Categories
Coarse Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock