Chrysoprase Gemstone Information
About Chrysoprase - History and Introduction
Chrysoprase is a distinct gemstone quality variety of chalcedony quartz, a cryptocrystalline form of silicon dioxide. Chrysoprase is highly prized for its opalescent minty, apple-green color, which is especially unique and is owed to its distinctive coloring agent. Most green gemstones are colored by iron (tourmaline), chromium (emerald) or vanadium (tsavorite garnet), but chrysoprase derives its alluring color from nickel impurities, which form within otherwise colorless quartz crystal. Chrysoprase is considered to be one of the rarest and most valuable varieties of chalcedony quartz, second only to the rare green-blue gem silica, which is also known as 'chrysocolla chalcedony'.
The name 'chrysoprase' originates from the Greek words, 'chrusos' and 'prason', meaning 'gold' and 'leek', respectively; referring to its leek-green color and the presence of golden inclusions. Chrysoprase frequently occurs in quartz veins of nickel-bearing serpentine rocks and in weathered deposits of nickel ore materials. Chrysoprase, like all other varieties of cryptocrystalline quartz, is composed of crystals that are too fine to be seen as distinct particles, even under magnification. Unlike most chalcedony quartz varieties that are prized for their multi-colored patterns, chrysoprase is desired for its solid and vivid green color, which is reminiscent of the finest quality jade.
Chrysoprase can be easily identified through its chalcedony quartz properties and by its distinct light-green to apple-green color. With a hardness of 6.5 to 7 on the Mohs scale, jade is much softer and typically less translucent, which makes it easily distinguishable from chrysoprase. Prehnite has a similar color, but it is typically not nearly as vivid or intense as chrysoprase. Variscite is also known to cause confusion, but its luster is more waxy and it's significantly softer than chrysoprase. Chrysoprase can also be distinguished by distinct traces of nickel. In fact, the only other green gem colored by nickel is gaspeite; all other green gems are colored by iron, chromium or vanadium.
Chrysoprase deposits can be found in locations all around the world. Some of the most important sources include Australia, Brazil, Germany, Poland, Russia, South Africa, Tanzania, Zimbabwe, Madagascar, India, Kazakhstan and the United States (Arizona, Oregon and California). Previously, the mines of Frankenstein (Zabkowice) in Upper Silesia, Poland were the most abundant sources for gem quality chrysoprase, but today, Australia produces nearly 85% of the world's supply. Chrysoprase mined from Central Queensland (Australia) is considered to be some of the world's highest quality, with many specimens displaying translucency and color similar to that of fine quality jade.
Buying Chrysoprase and Determining Chrysoprase Gemstone Value Back to Top
Chrysoprase Color
Chrysoprase color can range from light, minty-green to intense deep, apple-green color. Deeper colors are considered more desirable, but once the color reaches a certain depth, the stone may be classified as 'prase', which is not as desirable as chrysoprase. Chrysoprase color can fade under prolonged exposure to heat or direct light, but in many cases, the color may be restored after absorption of moisture.
Chrysoprase Clarity and Luster
Chrysoprase is typically translucent to opaque. Translucent specimens are considered most valuable. When cut and polished, it has a vitreous to waxy luster. Most chrysoprase forms very clean with regard to clarity, but an uneven, cloudy distribution of color is quite common.
Chrysoprase Cut and Shape
Chrysoprase is typically cut en cabochon and is also very popular for gemstone carvings, including ornamental objects, cameos, intaglios, seals and insignia. The most common shapes include rounds, ovals, trillions, hearts and pears. Chrysoprase beads and tumbled stones are also quite popular, but these will typically be fashioned from lower grade materials.
Chrysoprase Treatment
Most chrysoprase today is completely untreated. However, imitations, such as dyed green agate, may be 'misadvertised' as chrysoprase.
Chemical Formula: |
SiO2, Silicon dioxide |
Crystal Structure: |
Hexagonal; microcrystalline aggregates |
Color: |
Green, apple-green |
Hardness: |
6.5 to 7 on the Mohs scale |
Refractive Index: |
1.530 to 1.540 |
Density: |
2.58 to 2.64 |
Cleavage: |
None; fracture - rough, brittle |
Transparency: |
Translucent to opaque |
Double Refraction or Birefringence: |
Up to 0.004 |
Luster: |
Vitreous to waxy |
Fluorescence: |
None |
Please refer to our Gemstone Glossary for details of gemology-related terms.
Chrysoprase: Varieties or Similar Gemstones:
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Chrysoprase belongs to the very large family of quartz gemstones, but more specifically, it is a variety of chalcedony quartz. For many years, chalcedony was thought to be a fibrous (as opposed to granular) variety of cryptocrystalline quartz, but more recently, it has actually been discovered to be composed of quartz and moganite; a polymorph of quartz. Quartz and moganite are very closely related silicates, but they do have slightly varying crystal formations.
There are many other closely-related varieties of gemstones and there are also a number of gemstones that appear similar but are unrelated with regard to species, including variscite, jade (jadeite and nephrite), prehnite and smithsonite. Chrome chalcedony is also often confused with chrysoprase due to color similarities, but chrysoprase is colored by nickel, whereas chrome chalcedony is colored by chromium.
Most Popular Similar or Related Gemstones and Trade Names:
Chrome chalcedony, chalcedony, agate, onyx, carnelian, bloodstone (heliotrope)
and jasper are some of the most popular closely related gemstones.
Lesser-Known Similar or Related Gemstones and Trade Names:
Dendritic agate, fire agate, sard, sardonyx and chrysocolla chalcedony (gem silica) are among the least-known closely-related gemstones.
Chrysoprase Gemstone Mythology, Metaphysical and Healing Powers Back to Top
Chrysoprase is said to help balance the conscious and unconscious realms of the mind. It carries very strong energy and crystal power, which can bring happiness, protection, success, friendship, good fortune and prosperity. Chrysoprase promotes inner-strength and courage. It was highly prized by Greeks, Roman and Egyptians alike for its many great powers and alluring soft color. According to Greek legend, chrysoprase ensured a happy marriage and good health, and its power was 'recharged' when placed out in the open during half-moons.
Physically, chrysoprase is said to be able to strengthen eyesight, reduce blood pressure and relieve pain from rheumatism. Chrysoprase is a powerful stone that brings poise, grace and mental dexterity. It is also thought to be able to reduce inferiority complexes and mend broken hearts by boosting self-esteem. Chrysoprase is stone of Cancer and is associated with the element of earth. It is ideal for opening, activating and energizing the heart chakra.
Disclaimer: Metaphysical and Alternative Crystal Healing Powers and Properties are not to be taken as confirmed advice. Traditional, Ceremonial and Mythological Gemstone Lore is collected from various resources and is not the sole opinion of SETT Co., Ltd. This information is not to replace the advice of your doctor. Should you have any medical conditions, please see a licensed medical practitioner. GemSelect does not guarantee any claims or statements of healing or astrological birthstone powers and cannot be held liable under any circumstances. |
Chrysoprase Gemstone and Jewelry Design Ideas Back to Top
Chrysoprase is a variety of chalcedony quartz, rendering it suitable for just about any type of jewelry application, including rings for everyday wear. It is most often used for cabochon designs or as ornamental gemstone carvings, such as cameos, insignia and seals. It is not as popular as 'chalcedony in the narrow sense', but it can still be very commonly found in many gemstone rings, pendants, necklaces, pins and brooches.
Although chrysoprase is considered to be one of the rarest and most valuable forms of chalcedony quartz, larger sized stones are very much affordable. Chrysoprase is perfectly suitable for both men and women as the colors of chrysoprase are gender-neutral and can range from light-green to deep, army-green, 'near-prase' color. Its slight translucency and soft glow looks especially stunning when set in silver, platinum and white gold mountings.
Note: Buy colored gemstones by size and not by carat weight. Colored stones vary in size-to-weight ratio. Some stones are larger and others are smaller than diamond by weight in comparison.
Chrysoprase Gemstone and Jewelry Care and Cleaning Back to Top
Chrysoprase is considered to be one of the harder gems. Since it has no cleavage, it is quite durable, but it can still be easily scratched by harder materials such as topaz, spinel and diamond. The color of chrysoprase can fade if exposed to direct sunlight or extreme heat for prolonged periods of time, so care should be taken to avoid any excess or direct exposure to harsh conditions, which can damage the color of your gemstones. Chrysoprase can be easily cleaned using warm, soapy water and a soft cloth or brush. Be sure to rinse well to remove any soapy residue.
Owing to the natural porosity of chrysoprase, it can be easily dyed or stained by the absorption of other chemicals and colors. Therefore, avoid the use of any harsh household chemicals, especially bleach, perfume and sulfuric acid. Always remove any gems and jewelry before exercising, playing sports or performing household chores. When storing chrysoprase gemstones, wrap them using a soft cloth and place them inside a fabric-lined box for added protection.
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