Definition
Oil Shale is a fine-grained sedimentary rock from which oil is extracted
Appinite is an igneous rock in which the crystals are so fine grained that individual minerals cannot be easily distinguished
History
Origin
-
-
Discoverer
Unknown
Unknown
Etymology
From Old English scealu in its base sense of thing that divides or separate
From the variety of Lamprophyre Greek lampros bright and shining + porphureos purple
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Medium Hardness Rock
Family
Group
-
Plutonic
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Opaque Rock