Definition
A ganister is a hard, fine-grained quartzose sandstone or orthoquartzite which is basically used in the manufacture of silica brick typically used to line furnaces and is a type of sedimentary rocks.
Pyrolite is an igneous rock consisting of about three parts of peridotite and one part of basalt
History
Origin
England
Pike County, U.S
Discoverer
Unknown
Unknown
Etymology
From gan′is-ter i.e a hard, close-grained siliceous stone, often forming the stratum which underlies a coal-seam
From the chemical and mineralogical composition of the upper mantle of the Earth
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Family
Group
-
Plutonic
Other Categories
Coarse Grained Rock, Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock