Identify with naked eyes: Be familiar with real jade. There are only two types of recognized real jade, jade and nephrite. Among them, the most expensive and popular jade (Burmese jade, Burmese jade, imperial jade and Hetian jade) is mainly produced in Myanmar, while small amounts of jade are also produced in Guatemala, Mexico and Russia. 75% of the world's jade is produced from jade mines in British Columbia, all of which are nephrite. Nephrite is also produced in Taiwan, the United States and Australia (in small quantities). 2 Be familiar with imitation jade. Materials used to imitate jade include: serpentine (also known as "new jade" or "olivine") prehnite star quartz grossular garnet (also known as "Transvaal jade") chrysoprase (also known as "Australian jade") "Jade" - mainly produced in Queensland and Australia) Malaysian jade (a kind of transparent quartz that can be permanently colored, often named after its color, such as ruby, topaz, sapphire, etc.) Dolomitic marble (also called "mountain jade", Mainly produced in Asia and often dyed into bright colors) New Zealand jade. The local Maori residents value greenstone and New Zealand greenstone very much. They divide greenstone into four categories according to color and transparency: kawakawa, ka. Kahurangi and īnanga, these three are nephrite, while the fourth, tangiwai from Milford Sound, although expensive, is considered to be a genuine jade. Real price Bao Wenyu. 3Observe the texture. If possible, you can use a 10x magnifying glass to observe the internal mechanism of jade. Can you see fibrous or granular, tangled textures like asbestos? If so, the jade may be genuine nephrite or jade. Chrysoprase, on the other hand, is a collection of microcrystals that appear uniform under a magnifying glass. If you see a layer-like texture under a magnifying glass, then your piece of jade may have one or even two layers of other things superimposed on it (sometimes merchants will superimpose a very thin layer of jade on other stones to achieve the purpose of confusing the fish with the pearl) ). Learn to spot deception. Even if you are holding a piece of real jade, there is no guarantee that it has not been tampered with. Common tricks include: dyeing, bleaching, adding polymer stabilizers, or layering it with other materials. Jade can be roughly divided into the following categories based on the degree of adulteration: Grade A: pure jade that has not been subjected to any manipulation (such as high-temperature processing or high-pressure processing) except for traditional processing steps (i.e., cleaning with plum juice and polishing with beeswax). . The color of this jade is pure and pure. Grade B: This jade is bleached to remove imperfections, centrifuged to inject polymers to increase transparency, and covered with a hard, clear plastic. This kind of jade is unstable and tends to fade over time because the polymer is easily damaged by heat and detergents. But no matter what, this kind of jade still maintains 100% natural color and is still 100% pure jade. Grade C: This kind of jade has been bleached and dyed. If it is exposed to strong light, body temperature and detergent for a long time, it will fade easily. Throw the jade up and catch it with your palm. The density of real jade is very high, so it actually weighs a little heavier than it looks. If the piece of jade you weigh in your hand is heavier than other jade of the same size, and there are no problems when you observe it, then it is most likely real jade. Of course, this method is not very accurate, but it is easy to implement and relatively scientific. In the past, gem dealers used this method to identify real and fake jade. Listen to the sound. Another traditional way to determine authenticity without measuring density is to listen to the sound. First listen to the sound of plastic beads hitting each other, then find a piece of jade that you have determined to be real jade, and gently touch it with the jade you want to test. If it sounds very similar to the sound of plastic beads just now, then the jade you are testing is probably fake; if the sound is deeper and louder than just now, then it may be real. Feel it with your hands. Hold the jade in your hand. Real jade should be cold and smooth, a bit like holding soap. It takes a while for real jade to warm up in your hands. This method is especially suitable for identifying jade stones of the same shape and size. Scratch test: Jade is very hard and can scratch glass and even metal. Nephrite jade is slightly softer, so incorrect testing methods may destroy a real piece of nephrite. In addition, even if the jade in the test can cut glass or steel plates, it may just be some particularly hard imitation jade, such as various green quartz and prehnite. Find a pair of dull scissors, press lightly on the jade, and then make a small mark. The scratches should be as close to the bottom of the jade as possible so that they are not too obvious. If there is elegance on the surface of the jade, this method cannot be used, otherwise the jade will be easily damaged. If you get a white scratch, just rub it lightly (the white powder may just be metal powder from the scissors) to see if there are still scratches? If there are still, then this piece of jade is unlikely to be real. Density test: Calculate density. The density of jadeite and nephrite is very high (jade is 3.3, nephrite is 2.95). Density is calculated by dividing weight (in grams) by volume (in cubic centimeters). Use alligator clips to pick up the jade. If the spring scale you bought does not come with alligator clips, use a thin string, rubber band, or hair tie to tie the jade stone. Lift the top of the spring scale and measure the gravity of the jade. Record gravity. Use a spring balance with units in grams, so the calculated gravity is in units of dynes. Gently immerse the jade in the water and record its gravity in the water. The alligator clips can touch the water surface and will not affect the weight measurement.
If you are still worried, you can try again with something like the rubber band mentioned above. However, since this test is based on the gravity difference between two measurements, no matter whether you use a thin string, a rubber band or a hair tie, their gravity will be canceled out in the final calculation of the gravity difference, so it will not affect the calculation result. Calculate the volume of jade. Divide the value obtained by weighing in air by 1000 (if you have a calculator, divide it by 981 for accuracy), then divide the value obtained by weighing in water by 1000 (or 981), and subtract the latter from the former result. result. In this way, the apparent weight of the jade in the water is subtracted from the weight of the jade in the air, and the result is the volume of the jade (buoyancy = pVG).
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