carbuncle

A deep-red or fiery colored garnet or other dark red precious stone, especially when cut cabochon.

With eyes like carbuncles, the hellish Pyrrhus […]

And I will make thy windows of agates, and thy gates of carbuncles, and all thy borders of pleasant stones.

A charge or bearing supposed to represent the precious stone, with eight sceptres or staves radiating from a common centre; an escarbuncle.

An abscess larger than a boil, usually with one or more openings draining pus onto the skin. It is usually caused by staphylococcal infection.

An unpopular or ugly building; an eyesore.