Definition
Norite is a mafic intrusive igneous rock composed largely of the calcium-rich plagioclase labradorite, orthopyroxene, and olivine
Trachyte is a grey fine-grained volcanic rock which mainly consists of alkali feldspar
History
Origin
Norway
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Discoverer
Unknown
Alexandre Brongniart and René Just Haüy
Etymology
From the Norwegian name for Norway, Norge
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