Transparency, also known as water head in traditional jade industry, is still in use today. With high transparency, it is said that the water head is good and long. Transparency is also an important factor to evaluate the quality of jadeite. Identification steps of jadeite products: 1. Visual inspection (with the help of magnifying glass) includes: color, luster, structural characteristics, transparency, feel (specific gravity, thermal conductivity, etc. 2. Instrument identification Microscope magnification inspection: structural features, surface features and internal features Refractometer: measuring refractive index (spot measurement) spectrometer: absorption spectrum balance: weighing and measuring specific gravity Ultraviolet infrared fluorescence instrument: detecting whether there is fluorescence. Color: Jade is rich in color, which other jade does not have. The shape and combination, depth and distribution characteristics of colors are ever-changing, and sometimes five colors can appear on the same piece of material. To sum up, jadeite has five colors: white, green, purple, yellow, red and black. The characteristics of various colors are different: 1) white. Common white jadeites are slightly gray, green or yellow, and some are slightly brown and look dirty; 2) Green, the common color of jadeite, is often called emerald, which can be divided into light green, dark green and dark green. Green is the best, followed by dark green. Can appear yellow-green, gray-green, blue-green and other variegated colors; 3) Purple, which can be light purple, pink purple, purple, blue purple or even close to blue; 4) Yellow and red are secondary colors; 5) Black is divided into two types, one is dark green and the other is dark gray to grayish black. Among them, green is the most precious to jadeite, and the jewelry industry has made a very detailed classification of jadeite green. In the identification, we should not only look at the color and tone, but also judge whether the color is positive or not, whether it is the color that often appears in jade, so as to distinguish similar jade; We should also pay attention to the combination and distribution characteristics of colors, whether they are in the form of silk mesh, distributed along microcracks, colored roots or floating on the surface, so as to judge whether the colors are artificially caused. Gloss and transparency: the luster of jadeite is glass luster, greasy luster or greasy glass luster, and the transparency is affected by many factors such as the particle size, bonding mode, cracks and color depth of its constituent minerals. Most jadeites are translucent to opaque. Transparency, also known as water head in traditional jade industry, is still in use today. With high transparency, it is said that the water head is good and long. Transparency is also an important factor to evaluate the quality of jadeite. Feel: the density of jadeite is greater than that of most green jadeite, and it feels like a thug when measured by hand; Jadeite has compact and delicate structure, high hardness, smooth polished surface and slippery feeling by hand. It feels cold to stick it on your face, lips or hands. In this way, other jadeites can be distinguished from some treated jadeites. Structure (direct observation with naked eyes or observation with magnifying glass): rotate jadeite slightly, and observe jadeite with light source, that is, the star-shaped, linear and flaky flash reflected by the cleavage plane and crystal face of jadeite minerals. Emerald with a particularly delicate texture will not appear emerald. White stone flowers or stone brain lumps are often seen in jadeite, and jadeite is often easy to observe nearby. The particle size and morphology, fiber interwoven structure and particle fiber interwoven structure can be observed by transmitted light. Observe surface features, such as polishing, crack characteristics and color distribution, orange peel phenomenon, etc. It is often necessary to use a microscope for more detailed observation. From the structural characteristics, we can judge whether the jadeite is true or false and whether it has been artificially treated. The structure of jadeite determines the texture, transparency and luster of jadeite, and it is also a decisive factor in quality evaluation. Hardness: large, 6.57, can scratch glass. 2. Conventional instrument identification microscope: observe the surface characteristics, polishing marks (orange peel effect is the characteristic of commodity B), cracks and their surrounding characteristics (such as crack shape, whether there is filler in the crack and its characteristics, the characteristics of mineral particles at the crack edge, the relationship between crack and color, etc. , and judge whether it has been artificially treated, the groove crack is the characteristic of commodity B, and the color distribution along the crack is the characteristic of commodity C); Internal characteristics, 1) Look for emeralds and stone flowers and observe their characteristics, especially good emeralds may not be obvious or even not, and B goods are treated with strong acid, but emeralds are not obvious or not obvious; 2) Observe the color distribution characteristics; 3) Structural features: The composition minerals of jadeite are columnar or slightly elongated columnar, which are nearly oriented or staggered. Interwoven structure is a typical structure of jadeite, which is of great significance in jadeite identification. 4) Inclusions: Due to the transparency of jadeite, internal inclusions are difficult to distinguish, and dark inclusions such as limonite, goethite and chlorite are often seen on the surface. However, after artificial treatment, inclusions are rarely seen. Refractometer: point measurement 1.65 1.67, general 1.66. Under the polarizer: Jade is a heterogeneous aggregate, which turns 360 under the polarizer. Everything is ready. Specific gravity test: 3.303.34, generally 3.33, which is greater than most similar jade. Luminescence: most natural jadeites have no fluorescence, and a few green jadeites have weak green or white fluorescence; Some pale yellow varieties can also show weak green fluorescence under long-wave ultraviolet light; White jadeite has no to weak yellow fluorescence under long-wave ultraviolet light; Light purple varieties have no to weak white fluorescence under long-wave ultraviolet light; Dark varieties are inert. The bleached and oiled jadeite has orange-yellow fluorescence, while the filled jadeite has no weak fluorescence reaction (yellow-green fluorescence with weak to medium intensity in the early stage of B), and the jadeite dyed red has orange-red fluorescence. Absorption spectrum: 437nm line (iron line) is the characteristic absorption spectrum of jadeite; Chrome green jadeite has characteristic bands or lines of 630, 660 and 690nm. The thicker the green color, the clearer the chrome line. If the green color is very light, the 630nm line is not easy to observe. Charles color filter inspection: natural jadeite does not change color under the color filter, while jadeite dyed with chromium salt is red, and jadeite dyed in recent years does not change color under the color filter. Identification points of artificially treated jadeite: 1) According to the color, jadeite (treated) is bright, uniform and dull, floating on the surface, with colorless roots, or in a silk mesh, or distributed among mineral particles or along cracks; 2) Look at the surface features, orange peel effect, cracks, etc. 3) Look at the structure, the emerald is not obvious or there is no emerald, the internal minerals are damaged, or there are artificial fillings in the cracks; 4) Looking at inclusions, natural inclusions were dissolved by acid or artificially added; 5) measure refractive index and specific gravity; 6) absorption spectrum.