Definition
Origin
Discoverer
Etymology
Class
Sub-Class
Group
Other Categories
Trachyte is a grey fine-grained volcanic rock which mainly consists of alkali feldspar
Alexandre Brongniart and René Just Haüy
From Greek trakhus rough’ or trakhutēs roughness
Durable Rock, Medium Hardness Rock
Fine Grained Rock, Opaque Rock
Appinite is an igneous rock in which the crystals are so fine grained that individual minerals cannot be easily distinguished
From the variety of Lamprophyre Greek lampros bright and shining + porphureos purple
Durable Rock, Medium Hardness Rock
Coarse Grained Rock, Fine Grained Rock, Opaque Rock