te·​trad·​y·​mite | \ tə̇‧ˈtradəˌmīt \
plural -s

Definition of tetradymite

: a mineral Bi2Te2S consisting of a telluride and sulfide of bismuth, sometimes containing selenium, being pale steel gray in color and of a metallic luster, and occurring usually in foliated masses (hardness 1.5–2, specific gravity 7.2–7.6)

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History and Etymology for tetradymite

Late Greek tetradymos fourfold, from Greek tetra- + didymos twin; from its occurrence in compound twin crystals

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“Tetradymite.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tetradymite. Accessed 28 Oct. 2020.

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