Definition
Origin
Discoverer
Etymology
Class
Sub-Class
Group
Other Categories
Gritstone or grit is a hard, coarse-grained, siliceous sandstone
Coarse Grained Rock, Opaque Rock
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