CARBUNCLE, in mineralogy, a garnet (q.v.) cut with a convex surface. In medicine the name given to an acute local inflammation of the deeper layers of the skin, followed by sloughing. It is accompanied by great local tension and con stitutional disturbance, and pain is often acute. A hard, flattened swelling of a deep-red colour occurs on the back, face or extrem ities. This gradually extends until it may become as large as a dinner-plate. Towards the centre of the mass numerous small openings form on the surface, from which blood and matter escape, and through which a yellow slough or "core" of leathery consistence can be seen. Carbuncle is apt to occur in persons whose health is depressed by mental worries, or chronic disease of the kidneys or blood-vessels, or diabetes. The best treatment is surgical.