Definition
Origin
Discoverer
Etymology
Class
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Other Categories
Limestone is a sedimentary rock composed mostly of calcite and aragonite, which are different crystal forms of calcium carbonate
From lime and stone in late 14th Century
Durable Rock, Medium Hardness Rock
Fine Grained Rock, Opaque Rock
Tephrite is an aphanitic to porphyritic textured, volcanic igneous rock
From Greek tephra, ashes from Indo-European base, to burn
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock