1 Definition
1.1 Definition
Trachyte is a grey fine-grained volcanic rock which mainly consists of alkali feldspar
Metapelite is an old and currently not widely used field geological term for a clay rich fine-grained clastic sediment or sedimentary rock, i.e. mud or a mudstone
1.2 History
1.2.1 Origin
1.2.2 Discoverer
Alexandre Brongniart and René Just Haüy
Unknown
1.3 Etymology
From Greek trakhus rough’ or trakhutēs roughness
From Pelos or clay in Greek
1.4 Class
Igneous Rocks
Metamorphic Rocks
1.4.1 Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
1.5 Family
1.5.1 Group
1.6 Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock