Carbuncle (/ˈkɑːrbʌŋkəl/) is another name for a deep red almandine gemstone that has been cut with a smooth, convex face in a method called cabochon.[1] Traditionally, the term referred to any red gemstone, most often a red garnet.[2]
Carbuncles and their chimeras have spanned three millennia. Intermingling red gems until the time of their crystal-chemical definitions at the end of the 18th century, they united, for commercial purposes, the various sardonyx and carnelian, garnets, ruby and spinel as an intrinsic common quality of their luminous dispersion magnified by artifacts. [3]
Although they share the same linguistic origin, this gemstone should not be confused with the medical term carbuncle, a type of abscess.