obsidian
obsidian[əbˈsɪdɪən]noun- [mass noun]a hard, dark, glass-like volcanic rock formed by the rapid solidification of lava without crystallization
黑曜岩
语源- mid 17th cent.: from Latin obsidianus, error for obsianus, from Obsius, the name (in Pliny) of the discoverer of a similar stone
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