a) A deep-red or fiery colored garnet or other dark red precious stone, especially when cut cabochon.
With eyes like carbuncles, the hellish Pyrrhus...
b) An abscess larger than a boil, usually with one or more openings draining pus onto the skin. It is usually caused by bacterial infection.
And I will make thy windows of agates, and thy gates of carbuncles, and all thy borders of pleasant stones.
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