Black onyx is basically a fine-textured black chalcedony quartz. Onyx naturally comes in many colors, usually banded, and often brown varieties are dyed black. Its smooth silkiness gives the translucent stone a vitreous luster that makes it perfect for matching with opaque and clearer gemstones. Onyx typically comes in colors of white, tan and brown which are enhanced to bring out darker hues or even dyed completely.
Other colors of Onyx are often used together in intarsia style jewelry where the pieces are fit puzzle-like to create an image or symbol. The natural colors of Onyx for this use may include mother of pearl, green aventurine, and coral in floral designs. This method is also used in displays and to make decorative jewelry and trinket boxes, sometimes of soapstone.
Black Onyx plays nicely with many other stones. It is often matched with earthy tones like tigerâ€™s eye, jaspers, fossil stones, and amber, but also brighter organics such as malachite, turquoises, coral, sugilite, moonstones, and jades. Because of this ability to show off and play up so many other gemstones, Black Onyx is set in silver, gold, and tri-metal fittings, used in beaded jewelry and menâ€™s jewelry, and in modern and free-form styles. Inlays and intarsia often use this versatile stone to enhance designs and patterns in displays and artwork alike.
For winter, Black Onyx may be paired with hematite, quartz, or crystals and can replace costlier jet in many pieces. This classic compatibility makes a rather ordinary stone valued by both jewelers and owners. This is one of the few exceptions to faceting, as Black Onyx can be found in cabochon and round styles as well as square and marquise cuts and faceted. While the stone has enjoyed popularity in marcasite and Victorian jewelry, Black Onyx is also known as a mourning stone.