Carbuncle (gemstone) used by the Greek to translate the Hebrew נֹפֶךְ ("nōphek") in two of its four occurrences in the Old Testament. The etymology of the Hebrew term is uncertain, though Koehler-Baumgartner suggests a connection to פּוּךְ ("phook"), used in the Old Testament as a term for eye makeup, and probably implying a colored powder most likely made from a crushed mineral. For נֹפֶךְ ("nōphek") itself they suggest the gloss "semi-precious stone" (of uncertain color). Carbuncle (gemstone) A carbuncle is any red gemstone, most often a red garnet. The word occurs in four places in many English translations of the Bible. The
Tension ring for forming metal compression-spring gemstone mounting. Patent 5,188,679 is for the actual metal compression-spring gemstone mounting, i.e., the outcome of the method patented by Kretchmer. Tension ring A tension ring is a type of finger ring in which the gemstone is held in place by pressure rather than prongs, a bezel or other mounting. The metal setting is actually spring-loaded to exert pressure onto the gemstone, and tiny etchings/grooves are added to the metal in order to create a shelf for the gemstone's edges to rest. The gemstone appears to be suspended in the air with nothing holding it in