Definition
Origin
Discoverer
Etymology
Class
Sub-Class
Group
Other Categories
Slate is a fine-grained, foliated, homogeneous metamorphic rock derived from an original shale-type sedimentary rock composed of clay or volcanic ash through low-grade regional metamorphism
From Old French esclate, from esclat (French éclat)
Durable Rock, Medium Hardness Rock
Fine Grained Rock, Opaque Rock
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.
From gan′is-ter i.e a hard, close-grained siliceous stone, often forming the stratum which underlies a coal-seam
Coarse Grained Rock, Fine Grained Rock, Opaque Rock