porphyry

From Old French porfire, from Ancient Greek πορφυρίτες λίθος ("purple stone").

• IPA^(key): /ˈpɔɹfɪɹi/

porphyry (countable and uncountable, plural porphyries)

1. (geology) a hard igneous rock consisting of large crystals in a fine-grained matrix
   1. A purple-red rock of this kind.
      • 1980, Colin Thubron, Seafarers: The Venetians, page 43:

        A quartet of porphyry warriors, locked for all time in stern embrace outside St. Mark's Basilica, were probably carved in the Fourth Century. They are believed to represent the Roman Emperor Diocletian and the three men who held power with him.

• porphyrous
• porphyry shell