Scoria

Scoria / noun :

First Page Mentioned (By Name) : ch. “Condemned Complex” – pg. 72

Scoria is a porous igneous rock that's almost sponge like in appearance. Unlike pumice, its specific gravity is always 1 or greater, which prevents it from floating in regular water. This difference is caused by larger holes, and thicker walls between these holes (or vesicular cavities), a result of it forming through rapid cooling and depressurization of a low viscosity magma. Scoria is primarily comprised of glassy fragments, with a crystal content that varies greatly from source to source. It's usually dark in color (black or red), and tends to be basaltic or andesitic in composition.

Where you find scoria, you are also likely to find other metamorphic and igneous rocks, such as pumice and basalt, all three of which Geb has plenty.

Related Entries: Basalt; Geb (The Island Of); Igneous Rock; Metamorphic Rock; Pumice

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