Who can give me some information about "identifying" jewelry?

Professional knowledge about K gold, platinum, gold, diamond, jade, etc. Or may be a method for identifying authenticity. Thank you~~~~~~~~~

3 thoughts on “Who can give me some information about "identifying" jewelry?”

  1. Inlaid jewelry is a major category of jewelry. At present, there are two kinds of inlaid jewelry in the market. One is natural gems, such as emerald, diamond, ruby, emerald, cat's eye, sapphire, or Emerald Diamond jewelry, which is a precious decoration. Another kind of artificial gems, such as synthetic diamonds and artificial cats...
    inlaid jewelry is a major category of jewelry. At present, there are two kinds of inlaid jewelry in the market. One is natural gems, such as emerald, diamond, ruby, emerald, cat's eye, sapphire, or Emerald Diamond jewelry, which is a precious decoration. Another kind of artificial gemstone, such as synthetic diamond, artificial cat's eye, synthetic ruby, etc. The biggest difference between natural gems and artificial gems is that the former is pure in color, while the latter is bright but shallow in color; The former will never fade, and the latter will fade with time. At present, the technology of synthetic gems has been able to confuse the real with the false. It is almost the same as natural gems in terms of color, transparency, optical and physical phenomena. For example, the prices of artificial diamonds, artificial corundum and gems commonly seen in the domestic market are also very expensive. However, synthetic gems can still be distinguished from experience. The biggest difference is that most synthetic gemstones are almost flawless, while natural gemstones are more or less flawed. Moreover, natural gemstones have growth lines inside, and the true and false can be distinguished according to the crystal growth lines. The growth patterns of natural gems are regularly arranged along the hexagonal crystal shape direction. Therefore, parallel straight lines can be observed in the gems. Sometimes they are obvious, visible to the naked eye, and sometimes they are hidden. They need paper to set off and can be observed with a magnifying glass. The growth pattern of synthetic gems is circular arc. It can also be distinguished from the appearance. The synthetic gems are obviously too regular and lack natural traces, no matter in the color, transparency or the performance of gemstone star. Natural gems are not, their luster flashes from the inside, and the color appears pure and deep. The value of natural gems is very high, and the price of synthetic gems is not cheap, so you should go to the jewelry store to buy inlaid jewelry. As for the so-called inlaid jewelry made of glass, plastic and other materials on street vendors, it has no value. It is just a decorative toy

    silver jewelry identification method

    people buy silver jewelry mainly for dressing; As gifts to relatives and friends; Personal wealth preservation

    how to judge the authenticity of silver jewelry? Many people have been cheated on this issue. The silver head ornament has the following main characteristics, we can judge according to these characteristics

    judging by specific gravity, the specific gravity of silver is 10.5, which is much larger than that of other silver white metals or alloys, for example, the specific gravity of lead is only 2.7

    sound judgment: silver is soft, and the sound made by falling on a hard object is weak, while other metals make a clear sound

    judging by color, the white color of other metals is different from silver white after all, especially after burning and cooling. After baking with fire, if it is real silver, the silver will not change; If it is fake silver, or low-quality products, it will turn black after barbecue. Another method is to drip nitric acid on the surface of silver jewelry. After the nitric acid is removed, the surface of the jewelry is still silver white, which indicates that the silver content is quite high; If the silver content is low, it will be gray black

    first, check the stamp. According to the provisions of the national standard "gb1187-8p", if the silver content is not less than 925 ‰, it is called 925 silver, and the silver 925 stamp is printed; If the silver content is not less than 990 ‰, it shall be called full silver, stamped with full silver, or stamped with 990 silver

    secondly, the higher the purity, the whiter the silver, and the surface is fine, uniform, shiny and embellished. If it contains lead, the surface is cyan gray; If copper is contained, the surface is rough and dry. The surface of the oxidized silver forbidden pipe has "black rust", but its color is black and bright, while lead, tin and copper have no luster

    as the density of silver is slightly higher than that of common metals, generally speaking, "aluminum is light, silver is heavy, and copper is neither light nor heavy." Therefore, we can make a preliminary judgment on whether it is silver. In addition, the hardness of silver is lower than that of copper, but larger than that of lead and tin. Therefore, the surface of the object can be slightly scratched with a pin for testing. If there is a trace but it is not obvious, it can be preliminarily determined as silver jewelry

    as for the common Weizao silver in the market, manager Zhao said that Weizao silver is generally made of white copper, lead, tin, aluminum, etc. its characteristics are: the appearance of white copper is gray white, the stubble is brick gray, and green rust; The lead is gray blue, soft, and can be marked with nails; Tin is silver white and soft; Aluminum is white gray, soft and light in proportion

    how to identify jadeite

    collection and appreciation of jadeite and identification of goods a, B and C

    I. Burmese jade is also called jadeite jade. It was once popular at the end of the Qing Dynasty and the beginning of the Republic of China: for example, a jade plume tube made by Rong Lu, the Minister of the interior of the Qing Dynasty, was worth two taels of gold. In the mid-1930s, Tieyu Pavilion, the Jade King in Beijing, had a pair of bracelets, which were sold to Du Yuesheng in Shanghai for silver yuan. Due to the high hardness of Myanmar Jadeite Jade (also known as water species), it is bright and bright. Moreover, good jade essence is bright and peaceful, and has high value of preservation and collection, so it is called "king of jade". It is loved by many people who love jade and wear jade. Japan and New Zealand also regard jadeite as their "national stone". Due to the special geographical relationship that jadeite jade is produced in Myanmar, which is close to China, and most of the finished products are processed in China, and the special preference of Chinese people for jadeite jade, Western countries also generally believe that jadeite is Chinese "National jade.

    2. The color of jadeite jade in Myanmar. The color of jadeite jade in Myanmar is slightly different due to different regional customs. In the jade kingdom of Myanmar, jadeite is divided into three categories and 12 grades. The domestic jewelry industry subdivides it into more than 30 grades according to its different colors. In general, the color tone of jadeite jade in Myanmar can be roughly divided into the following six categories.

    1. White. Basically, it does not contain other impurity elements.

    2. Red. Chemical element containing iron (FC3)

    3, green. Chromium containing more than 2 < Cr > commonly known as Cui >

    4. Black. Chromium (CR) and iron (Fe2) containing more than 2

    5, purple. The element containing chromium (CR), iron (FE) and cobalt (CO)

    in particular, the green in Myanmar jade can be worn regardless of identity, status, age and gender, except for its bright color and excellent durability. Therefore, it is very consistent with the Chinese people's implicit, peaceful, gentle and friendly character. Social demand is increasing. Prices have also multiplied, or even increased a hundred times. At present, the price of a green bracelet on the international market has reached more than 10 million yuan. Even the Burmese jade jewelry with a slightly lower green color is not cheap as long as it is genuine A-goods, with sufficient water head, clear technology and coordinated color

    III. The quality and identification of Myanmar Jadeite. Good jadeite is very limited in terms of mineral reserves and mining volume of Myanmar jade. Therefore, some speculators and profit-seeking businessmen "take advantage of the scarcity" to enter. A large number of counterfeits are sold to make profits. Even in the jade kingdom of Myanmar, fake goods are everywhere; Fake stones and ornaments can be seen everywhere

    the types of Burmese jade that are popular in the market at present are divided into the following four categories according to the level of authenticity:

    a goods are both natural texture and natural color. The identification method is based on the following three points:

    (1) think twice and act carefully. Due to the relationship between mineral resources and mining volume and the specific conditions of large demand, there are few good Myanmar jade in the market at present. In particular, there are few varieties with green color and bright ground

    (2) generally, varieties such as seedling green, broccoli green, emerald or violet floating flowers are common

    (3) under the light, the texture is fine, the color is soft, and the stone grain is obvious; Slight impact, clear and pleasant sound; There is a heavy feeling in the hands, which is obviously different from the rest of the stone

    the jadeite jade with black spots, commonly known as "dirty", will be soaked and corroded with strong acid to remove dirt and cotton, increase transparency, and then epoxy resin will be injected into the micro cracks caused by strong acid corrosion under high pressure to fill the cracks

    (1) the color of B is good at the beginning of the goods. After careful observation, the color is hanging and evil. When observed under the lamp, the color transparency is weakened

    (2) goods B gradually lose luster and become ugly with cracks in two years. This is caused by the deterioration of its original quality by strong acid

    (3) decreased density and weight. Slight impact, the sound is dull, and the clear sound of a goods is lost

    the color of goods C is completely manually injected

    (1) at the first sight, the color is not correct and evil

    (2) when viewed under the lamp, the color does not naturally exist in the interior of the jadeite crystal, but is filled in the cracks of the mineral, showing a network distribution without color roots

    (3) when observed with Charles color filter, green turns red or colorless

    (4) the surface color can be removed or changed to brown by scrubbing with strong anti-aging agent

    there are two main categories of d goods, which are fake jadeite jewelry

    (1) jade. That is to say, other Jadeites pretend to be Jadeites. There are mainly Thai Cuiyu, Luxia Cuiyu, Nanyang Dushan jade, Qinghai Cuiyu, Miyu, Australian green jade and Dongling stone. The differences between the above jadeite and Myanmar Jadeite are: low hardness, low density (light weight) and weak luster

    (2) green glass and green plastic. Most of these substitutes are dull and unsightly, with weak luster. The relative density is very light, the hardness is low (it can be carved with nails), and there is no cold feeling

    identification of diamonds

    perspective test - clean the gemstone with round diamond cut, place it on a piece of white paper with a line drawn, and observe the line on the paper through the gemstone to determine whether the gemstone is a diamond. If it is a standard round diamond cut diamond, the line on the paper cannot be seen through the diamond (artificial strontium titanate and synthetic rutile are similar to diamonds and have no perspective effect). However, most of the imitations do have enough light leaking out of the pavilion facets due to different refractive indexes, and a part of the lines on the paper can be seen through perspective observation

    brightness intensity estimation - the ability of the crown of a gemstone to reflect the external light and refract the light through internal total reflection, which is called brightness. The diamond and its imitation are placed in the same environment with the same light source and the table top is upward. For the standard round diamond with fine cutting, almost all the light entering from the crown is reflected from the crown, showing extremely strong brightness. However, the imitation confirms that the refractive index and cutting are different from the diamond, and the light entering from the crown will leak out from the pavilion to varying degrees, thus reducing the brightness

    oil test - use a special pen or ball pen with oil-based ink to draw a line on the diamond table, and an uninterrupted straight line will be left. While other imitations do not have lipophilicity, leaving intermittent dotted lines at the scribe line

    water drop test: clean the diamond and the imitation table, drop a small drop of water each, and observe the retention time and contour of the water drop. The water droplets on the diamond will remain spherical for a long time, while the water droplets on the replica will disperse in a relatively short time

    haze test - place the sample to be tested and the known diamond sample on the glass, and breathe against them to observe the disappearance of fog. The fog on the diamond will disappear quickly, while the fog on the imitation will disappear slowly

    sensory test - when the tip of the tongue touches the diamond and its imitation at room temperature, the diamond is much cooler than the imitation

    instrument identification

    amplification detection - observation under a magnifying glass or gemstone microscope. (1) In addition to high quality, diamonds generally contain a small amount of micro mineral inclusions. Common inclusions include more than 30 kinds of black graphite, brown spinel, red chrome spinel, magnesia alumina garnet, and colorless olivine. (2) Due to the rarity, rarity and high hardness of diamonds, the cutting and grinding of diamonds are very careful. The cutting ratio, crown and pavilion angle of diamonds are calculated. The mesa and small facets of the diamond are straight without buckling. The edges and corners are straight and sharp. Three or more edges are strictly intersected at one point. However, due to the low hardness and poor cutting, the edges and corners are often smooth. (3) The extremely high hardness of diamond makes it difficult to be worn, even if the wear is limited to the edges and corners of individual small facets. However, the imitation is often rough after being worn due to its low hardness

    thermal conductivity tester - the thermal conductivity tester can quickly, easily and accurately distinguish diamonds and their imitations, especially for the identification of inlaid diamond jewelry. Different materials have different thermal conductivity, and the thermal conductivity of diamond is the best among gemstones (thermal conductivity is 1000-2600w / m. ℃). Contact the probe head of the thermal conductivity meter with the sample, turn on the power supply, and according to the heat transfer speed of the thermocouple, the number of lights displayed by the light emitting diode or the text displayed on the liquid crystal screen can be used to know the true weight of the diamond

    reflectometer test - the advantages and disadvantages of the reflectometer and the thermal conductivity meter are exactly complementary, that is, the gems easily confused on the thermal conductivity meter can be clearly distinguished on the reflectometer, while the gems with similar characteristics on the reflectometer can be clearly distinguished by the thermal conductivity meter

    X-ray fluorescence testing - the application of X-ray in gemstone identification is very important. X-rays are high-energy rays, which will cause damage to the crystal lattice of gems and change the color of gems. Generally, this identification method is not used

    electronic balance or other scales - it is a very effective and simple way to distinguish the density of bare drill and imitation drill with electronic balance or other scales. The density of diamonds (3.529 g / cubic centimeter) is quite different from that of most imitations. Only the density of natural Topaz (3.56 g / cubic centimeter) is similar to that of diamonds

    the difference between diamonds and imitation stones

    the difference between diamonds and natural colorless gemstones - the gemstone most similar to diamonds is zircon, because the colorless zircon also has a large refractive index and dispersion, and the processed zircon also has a radiant appearance, so it is one of the best natural substitutes for diamonds. The difference between diamond and zircon is actually very simple. Diamond is an equiaxed gemstone without polarization and birefringence, while zircon has polarization and great birefringence. When you look down from its crown, you will find that one edge has changed into two, that is, "double shadow" phenomenon, while diamond is still an edge. In addition, it is easy to distinguish by hardness method. Just engrave the gemstone to be identified with a synthetic sapphire. If it can make a mark, it is a diamond; if it slips and cannot be scratched, it is not a diamond. Other natural colorless gems often have a small refractive index, so even if they are well cut and ground, it is difficult to have the appearance of "radiant" and "colorful guests". The refractive index of diamond is 2.42, which is beyond the reading range of ordinary refractometer. However, it is easy to measure the refractive index of ordinary gems, such as colorless Topaz and crystal (if other characteristics are similar to diamonds, the refractive index is generally not measured to avoid scratching the refractometer). In addition, the processing of general gems is often not strict, and light leakage often occurs. However, larger diamonds (such as more than 30 points) are often processed strictly because of their high value, and generally do not leak light

    the difference between diamonds and artificial imitation diamonds - another kind of fake that is most similar to diamonds is cubic oxidation milling, or CZ for short. Because this synthetic gemstone was first developed by the Soviet Union and is very similar to diamonds, many people call it "Soviet diamond" (it is worth noting that some people think that the diamonds of the Soviet Union are fake, but the Soviet Union is also a large country with natural diamond resources). Cubic zirconia belongs to the equiaxed crystal system, with hardness as high as 8.5, and refractive index and dispersion are also large. The processed "Soviet diamond" also has an attractive appearance of sparkle, and sometimes its "beauty" even exceeds that of natural diamonds with poor processing. It is not difficult to distinguish natural diamonds from other artificial imitation diamonds. (1) The hardness of all synthetic products is lower than 9. For gemstones without setting, it can be distinguished by the method of scoring the hardness. It is diamond that can score synthetic sapphire, and it is not diamond on the contrary. This method can also effectively distinguish some surface coated glass imitations. (2) Generally, the color of artificial substitutes is very "white" and clean, while natural diamonds, except for some high-end products with 96 colors and above VVS, mostly have some yellow tones and some "defects" can be seen. (3) Synthetic substitutes are low in hardness and low in price, so the processing is rough, and the gems often "leak light" and appear "rough edges" or rounded edges

    the distinction between diamond and artificial diamond, modified diamond and Sandwich Diamond - the third type of fake is artificial diamond. It often has almost the same physical properties as natural diamond, such as hardness, refractive index, dispersion, etc. it is impossible to distinguish them by sensory perception alone. A simple distinction is that synthetic diamond usually contains some metal mineral inclusions, which will have "magnetism", while natural diamond has no magnetism. The method is: put a magnet in front of the microphone, move the diamond in front of the microphone quickly, and the synthetic diamond will produce a small sound, indicating magnetism. The color of diamonds was changed after the radioactivity of "radium" was discovered at the beginning of this century. Color diamonds with good color are more valuable than colorless diamonds, thus promoting the development of the technology of changing light brown or yellowish diamonds into color diamonds. It has become a must to distinguish between natural and color diamonds. When viewed from the table top of the artificial color drill (produced by radiation or high-energy accelerator bombardment), some umbrella shaped color circles or shadows will appear, and there will be 594nm characteristic absorption lines in the absorption spectrum. In addition, its fluorescence, radioactivity and conductivity are different from those of natural color drill. Sandwich diamonds are mainly because of the special shape of raw materials. Artisans often "combine" two originally small diamonds into a larger diamond. Some use diamonds as the top and crystals or colorless synthetic corundum as the bottom to make a two-layer "diamond". When inlaying, they use "gold claws" or "gold edges" to block the bottom layer and deceive the customer. For this kind of diamond, you can use a magnifying glass to carefully observe whether there is a bonding interface at the qisaibu. You can often see some small bubbles and glue, or you can feel a layer of mist on a certain layer inside the diamond. If the gemstone is not inlaid, the effect will be better if it is put into diiodiomethane or water for observation

    the distinction between diamonds and coated diamonds - the fourth type of counterfeit, coated diamonds may

  2. Systematic gemology is relatively expensive.
    you can buy gemology tutorials that are sold in large quantities, which are relatively simple and easy to get started

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