Definition
Trachyte is a grey fine-grained volcanic rock which mainly consists of alkali feldspar
Ignimbrite is a volcanic rock consisting mainly of pumice fragments, formed by the consolidation of material deposited by pyroclastic flows
History
Origin
-
New Zealand
Discoverer
Alexandre Brongniart and René Just Haüy
Patrick Marshall
Etymology
From Greek trakhus rough’ or trakhutēs roughness
From Latin ignis fire + imber, imbr- shower of rain, storm cloud + -ite
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
Family
Group
Volcanic
Volcanic
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock