The gemstone Chrysoprase is an opalescent green colored variety of chalcedony, and is the rarest of the group. Most green stones get their color from chromium or vanadium, but chrysoprase derives its color from nickel. Often confused with jade, chrysoprase is one of the most expensive semi-precious stones with an apple green color.
Hardness: As with all forms of chalcedony, chrysoprase has a hardness of 6 – 7 on the Mohs scale of hardness.
Color: Chyrsophase is most often found in an apple-green color, but the green color varies from light to dark green. The darker varieties of chrysoprase are often referred to as prase. Chrysoprase is quite often opaque, but the more translucent the gemstone, the better the quality. Many of the chrysoprase gems used for beads have a brownish matrix. Unfortunately, chyrsophase is susceptible to heat and over-exposure to the sun has been known to lighten the color.
Birthstone: Chrysoprase is the alternate birthstone for May. It is also one of the star signs for Gemini and the ancient Russian birthstone for December.
Scarcity: Chrysoprase is rare because it is a cryptocrystalline. To have this property means that instead of being formed by large six sided crystals, the size of the crystals are extremely small and invisible to the naked eye.
Value: The value of natural chrysoprase can vary greatly depending on the size and quality of the gemstone. The highest-quality material is a highly saturated, rich apple-green of even color, without flaws, fractures, inclusions, cavities or other imperfections. Custom cut stones are more valuable than calibrated cuts and larger pieces of high quality are rare. The most highly prized stones come from Australia, although low quality pieces can also be found there.
Most Common Cuts: Chrysoprase is generally made into beads or spherical objects. More rarely it is cut into cabochons.
Chemical Formula: The chemical formula for chrysoprase is SIO2.
Synthetic Varieties: Before large quantities of the stone were discovered in Australia, dealers compensated for the gem’s scarcity by staining colorless quartz green, using either nickel salts or chromium salts. These fakes were often not recognized by the general public.
History: Chrysoprase has been referred to as early in history as 23 A.D., but was not mined commercially until 1740. Chrysoprase was most often used by the Greeks, Romans and Egyptians in jewelry and other ornamental objects. Prussian King Frederick the Great adorned his palace with objects and furniture made of chrysoprase. He also wore a ring that was set with a large chrysoprase surrounded by fifteen brilliant stones and carried a walking stick with a chrysoprase knob. During the middle ages, it was mined in Silesia (Northern Czech Republic and Southern Poland), and Europeans coveted Chrysoprase for its wonderful color. They used the stone to adorn churches and other important buildings.
The best known sources of chrysoprase are Australia, Germany, Poland, Russia, Arizona, California and Brazil. Australian chrysoprase is most likely the reason for renewed interest in the gem over the past few years. The finest and most abundant deposits are found in the Queensland region.
Rumored Healing Properties: The healing powers of gems remain a controversial issue, but healers have touted their power for centuries. Chrysoprase is said to speed the healing of any wound, shield one from negative energy, and help bring the unconscious to light. It strengthens the workings of insight, encourages hope and joy, helps clarify problems, has been used as a cure for restlessness and serves as protection on voyages.
Chrysoprase has also been used to prevent depression, increases grace and equilibrium and help with fertility. In the middle ages, many believed that if you put a piece of chrysoprase in your mouth, you would become invisible, and Romanian folklore claims chrysoprase enabled its owner to understand the language of lizards. It also is said to relieve gout, eye problems and mental illness.