Definition
Origin
Discoverer
Etymology
Class
Sub-Class
Group
Other Categories
Trachyandesite is an extrusive igneous rock.
From French trachyandésite, trachy + andésite andesite, a lava intermediate in composition between trachyte and andesite
Durable Rock, Medium Hardness Rock
Fine Grained Rock, Opaque Rock
Nephelinite is a fine-grained or aphanitic igneous rock made up almost entirely of nepheline and clinopyroxene (variety augite).
from French néphéline, from Greek nephelē
Fine Grained Rock, Opaque Rock