Definition
Oil Shale is a fine-grained sedimentary rock from which oil is extracted
Tephrite is an aphanitic to porphyritic textured, volcanic igneous rock
History
Origin
-
Germany
Discoverer
Unknown
Van Tooren
Etymology
From Old English scealu in its base sense of thing that divides or separate
From Greek tephra, ashes from Indo-European base, to burn
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Hard Rock
Family
Group
-
Volcanic
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock