Definition
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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
Ijolite is an intrusive igneous rock which is composed mainly of nepheline and an alkali pyroxene, usually aegirine-augite
From the first syllable of the Finnish words Ii-vaara, Iijoki, &c. commonly used geographical names in Finland, and the Gr. Xiflos, a stone
Durable Rock, Medium Hardness Rock
Coarse Grained Rock, Opaque Rock