Definition
Origin
Discoverer
Etymology
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Other Categories
Scoria is a dark-colored extrusive igneous rock with abundant round bubble-like cavities
From late Middle English (denoting slag from molten metal), from Greek skōria refuse, from skōr dung
Durable Rock, Medium Hardness Rock
Fine Grained Rock, Opaque Rock
Trachyandesite is an extrusive igneous rock.
From French trachyandésite, trachy + andésite andesite, a lava intermediate in composition between trachyte and andesite
Durable Rock, Medium Hardness Rock
Fine Grained Rock, Opaque Rock