Definition
Origin
Discoverer
Etymology
Class
Sub-Class
Group
Other Categories
Oil Shale is a fine-grained sedimentary rock from which oil is extracted
From Old English scealu in its base sense of thing that divides or separate
Fine Grained Rock, Opaque Rock
Adakite is an intermediate to felsic volcanic rock that has geochemical characteristics of magma which is said to be formed by partial melting of altered basalt that is subducted below volcanic arcs
From Adak, Aleutian Islands
Durable Rock, Medium Hardness Rock
Fine Grained Rock, Medium Grained Rock, Opaque Rock