Definitions
Dark volcanic glass formed when lava cools very quickly.
Word origin
From Latin obsidianus; named after Obsidius, who was, according to Pliny, the Roman who discovered the stone in Aethiopia.
Used in a sentence
“Looks like a yellow biscuit of a buttery cue ball moon / Rolling maverick across an obsidian sky”
Source: Wiktionary, CC BY-SA 4.0
Used as a crossword answer1 curated clues
01“Dark volcanic glass”8 letters
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