Today's WORD-A-DAY: CABOCHON

CABOCHON (pronounced ca-bo-shon'). A cabochon is a gem which is polished to a convex shape, rather than faceted. Cabochon polishing dates to ancient times, whereas faceting only began appearing in the Middle Ages. There are some sorts of stones (mostly the semi-precious variety), such as cat's eye, moonstone, and turquoise, which are almost always polished as cabochons. Precious stones are sometimes polished as cabochons, and star sapphires and rubies are always cabochons. Pictured here is a sapphire cabochon set in a platinum and diamond art deco ring.