Chalcedony is a translucent variety of microcrystalline quartz that occurs in a range of colors similar to jade. Chrysoprase is a bright green chalcedony colored by chromium that, when cut into cabochons, beads, and small sculptures, will look very similar to jade. Chalcedony occurs in a variety of other translucent colors such as black, lavender, yellow, and orange that can look like the color varieties of jade.
Chalcedony can be a very close gemstone look-alike with jade. It can be differentiated from jade using is lower specific gravity and by a variety of instrumental methods. Serpentine occurs in a variety of wonderful translucent to nearly transparent green and yellowish green colors that look very much like jade.
It is a metamorphic mineral that is often found in the same geographic areas and same types of rocks as jade. Serpentine is significantly softer than jade and also has a much lower specific gravity. Vesuvianite has a color and a greasy luster that fool unknowing people into thinking it is nephrite. Vesuvianite , also known as idocrase, is another jade look-alike that is very difficult to distinguish from jade without laboratory testing.
It has similar hardness , specific gravity, and physical appearance. Vesuvianite is not nearly as tough as jade and will break more easily - but that requires destruction of the specimen.
Maw Sit Sit is a rock composed of jadeite, albite, and kosmochlor a mineral related to jadeite. It has a bright chrome-green color and accepts a bright polish. For those reasons it is used as a gemstone.
Maw sit sit was first properly identified in near the village of Maw Sit Sit in northwestern Burma in the foothills of the Himalayas. This is the only location where it has been discovered to date. It is used to cut cabochons and produce small sculptures. Because of its scarcity and low production, it is rarely seen in jewelry. Maw Sit Sit is a rock with a bright chrome-green color mined in Myanmar.
It has a very similar appearance to jade. Maw sit sit is composed of jadeite, albite, and kosmochlor a mineral related to jadeite. It is used to cut cabochons, beads, and make small sculptures, and is easily confused with jade. Hydrogrossular Garnet is a green massive variety of garnet that is usually green in color with black markings.
It looks so much like jade that in South Africa, where it is common, it is known as "Transvaal Jade. Aventurine is a trade name used for a green quartz that is often colored by fuchsite inclusions.
These typically color the quartz a light to dark green color and produce some aventurescent sparkle. Aventurine is sometimes confused with jade.
It is sometimes referred to by the misnomer of "Indian Jade. All of the above natural minerals and rocks can be confused with jade. Many people like them, enjoy them, and knowingly purchase them for that reason. It is important to know that these jade look-alikes, along with plastic and glass made into objects in the same style as jade, are abundant in the market place. Know what you are buying or purchase from a dealer you can trust if you are shopping for these items and desire jade instead of an alternative.
Errors and deception are common. British Columbia jade cabochons: A pair of translucent cabochons cut from bright green British Columbia nephrite. Approximately 10 x 12 millimeters in size. Today, tons of jade are mined in British Columbia and shipped to China, where both demand and prices are higher than in western Canada.
Most people immediately think of China as the source of jade and jade objects. China has always been an important producer of jade, a leading jade cutting center, jade consumer, and jade market. The only time dominance in these activities moved outside of China was between World War II and the early s. At that time the Chinese government suppressed jade commerce, and Hong Kong temporarily became the center of jade commerce. Jade jewelry and jade artwork are extremely important in China.
Jade is more important in China than the importance of diamonds in the United States. Per-carat prices for the best imperial jade in China rival the per-carat price paid for diamonds in the United States. Since prehistoric times, jade has been used to make tools, weapons, and important ornamental objects in Asia , Europe , Australia , North America , South America , and numerous Pacific islands. The toughness of jade made it an excellent material for making tools and weapons.
Because of its beauty, people held jade in highest esteem and used it to make religious art and ornaments for their rulers. None of these ancient cultures had contact with one another, yet they all independently used jade for many of their most sacred and important objects. Such is the appeal of jade. Green Jadeite Boulder: An alluvial boulder of green jadeite with a brown weathering rind from northern Burma.
This boulder is about 6 centimeters across. Photo by James St. John, used here under a Creative Commons license. Lavender Jadeite Boulder: An alluvial boulder of lavender jadeite with a brown weathering rind from northern Burma.
This boulder is about 18 centimeters across. Jadeite and nephrite are minerals that form through metamorphism. Varying shades from white to dark green sometimes including purple, pink, red, yellow, orange, blue, and black. Master Craftsman from China worked with Jade that came from Burma at the time and this Jade is known for being harder, denser, and producing a higher luster once it's polished. It is this Jade that has become the preferred material among Artisans and most highly prized among buyers.
Today, commercial jadeite objects are divided into three types based on the treatment they have been exposed to during the manufacturing process. It's been a common procedure for thousands of years to find ways to improve the appearance of Jade objects through a variety of treatments that improve the stability, color, and luster. Some of these include injecting polymers, adding dye, bleach, acid, or applying heat. With this, manufacturers boil the finished jadeite objects in their final form in water and then clean them so that they are ready to be dried and dipped in molten wax.
The purpose of the molten wax is to fill in any minute fractures or pores on the surface. Any excess wax outside of these fractured areas is removed and the entire item is buffed to a higher luster. In effect, this smooths out any irregularities and gives a completely smooth finish to the surface of the object. The one downside to type B manufacturing for jadeite is that these objects can deteriorate within a few years.
The acid treatment makes them particularly brittle and the polymer resins can discolor when exposed to extreme sunlight or heat. Type C jadeite are objects that during manufacturing have been exposed to the same treatments as type B but have also been dyed to a specific color.
The color dye used for the type C manufacturing will fade with time and with extreme exposure to light and heat. Jade is made of specific minerals. Jadeite is a mineral that formed through the process of metamorphism which is associated with metamorphic rocks.
There are places around the world where jadeite deposits occur naturally usually along the geologic locations where tectonic plates meet. Most jadeite is found in rocks with a high level of pressure which forces the jadeite deposits to separate.
Historically, prospecting for Jade, the process of finding and retrieving it, was done in steeper areas of drainage basins, usually places where pieces of rocks were found in stream valleys ranging in size from small pebbles to large boulders. The pebbles in the boulders that contain Jade normally have brown weathering rinds around the exterior that mask the interior beauty. When searching for these Jade boulders, small windows are usually cut into the rock in order to determine the quality of the material inside.
Being able to look inside determines whether it's worth the effort of moving the rock from its location to be refined elsewhere. Depending on the size, it was very difficult to transport without damage. Historically human and animal labor were the only ways to move large boulders which is why it was so important to cut into the stone at the site before moving the boulder just to make sure it was worth the investment. Today however this remains the case in some areas where the equipment that one might use is simply unable to get into the location where the rocks are found.
However, in some cases, helicopters with baskets and slings are able to fly into otherwise difficult to reach areas and lower the sling on a cable to the ground where workers can prepare the boulders, move them in place and secure them at which time the helicopter can fly them out of the basin.
This is not something that is often used for smaller rocks but oversized boulders that can't be lifted up and carried out by hand. Because the helicopters used for this process are very expensive, the rock has to be a sound investment and in cases like this a single large boulder can be worth thousands of dollars and it's rough form, making it worth the investment. In other cases, Jade can be mined from the hard rock deposits left behind in different areas. In an area where large Jade boulders are found it might also leave behind traces of Jade in the rock deposit usually in ancient subduction zones which are now exposed thanks to the weather.
Jade has many imitations. There are dozens of stones out there like Serpentine, calcite, quartz, and prehnite all of which can look very similar to Jade. A trained eye should be able to identify the distinctive luster associated with Jade that isn't found with less valuable items like quartz or Serpentine. Quartz and Serpentine also lack the hardness of Jade so if you look at intricate carvings they might have extra stress fractures you might notice that multiple pieces had to be glued together because of how fragile the material is.
This is not the case with Jade products. When buying Jade jewelry , if there is no information on where it was from or the information doesn't tell you that it's from the rim of the Pacific Ocean, it might not be something you should invest in. The stone found above is believed to be jadeite, which is the most common form found in Myanmar and typically of higher quality compared to nephrite.
You'll notice the massive stone above looks rather dull compared to typical jade you see at a jeweler. Uncut and unpolished jade only has a slight dark green hue but otherwise appears rather dull. Once cut and polished, this jade stone will truly show its magnificence. Unfortunately, this impressive new find is shadowed by recent reports on corruption in Myanmar surrounding its jade business. Jade mining is frequently used as a front for financing military elites, drug lords and those in control.
Meanwhile, the general population never sees a cent of revenue from the lucrative mining industry. You can read more in this excellent report by Global Witness on the jade industry in Myanmar and the corruption surrounding it.
Just to make things even more confusing, in New Zealand, jade is called pounamu or greenstone. As one of the world's oldest decorative stones, jade has been prized for its beauty across the world. Close up of a carved nephrite slab, from Marsden River, New Zealand. Bown Collection Source: Geoscience Australia. The two jade minerals, nephrite and jadeite are both tough and have small granular crystals giving a fibrous appearance.
They have quite different chemical compositions and structures. Nephrite is a type of amphibole mineral and jadeite is a type of pyroxene mineral. Nephrite can be white, yellow, green and brown to black, depending on the amount of iron and magnesium in the mineral.
Jadeite can be green, pink, purple, brown and white. Nephrite jade is very tough, the toughest known natural mineral, three times tougher than ceramics and even tougher than steel. This explains why it was used in neolithic times for knife blades, axe heads and later for ornamental carvings. While it is not as hard as some other minerals like diamond, nephrite is made from an interwoven meshwork of fine fibres or needle-like crystals so is not brittle and does not break easily.
Coarser crystals and alignment of minerals decreases the toughness of the mineral. Jadeite is the second toughest mineral known, but is not as tough as nephrite as its interlocking crystals are less fibrous. The interlocking crystals or fibrous structures of these two jade minerals mean they can be polished easily, so are ideal for carvings and jewellery.
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