To identify the authenticity of gold ornaments, in addition to using gold medals, touchstones, eating Hu Jin and other tools and chemical methods, you can also use the following simple methods:
First, real gold jewelry is soft when it is bent by hand, and it is easy to bend and not easy to break. It is easy to straighten by hand friction, and there will be traces when scraping with hard objects; Fake gold, gilded, gilded or doped with low color, when bent by hand, is hard in quality, easy to break and not easy to bend.
Second, real gold jewelry will make a "click" sound when thrown on the table; Fake or poor quality is thrown on the table and makes a sharp sound, jumping higher than real gold.
Third, real gold jewelry is golden in color; Too deep red is imitation gold, and light color is mixed gold such as silver and aluminum.
Fourth, real gold jewelry can be burned fiercely and will not change color for a long time; Fake ones don't resist fire, they turn black and purple, and they don't look bright.
Methods should be used comprehensively to identify the authenticity.
Beware of being fooled when buying 18K gold jewelry.
At present, 18K gold jewelry is favored by consumers because of its low price, various patterns, bright luster, high hardness and easy setting of gems. However, the recent appearance of 18K gold ornaments marked "JP" or "JF" on the market has made many consumers cry and fall for it.
It turns out that according to the national regulations on gold jewelry, "JP" refers to gold-plated jewelry and "JF" refers to imitation gold jewelry. "18KJP" means 18K gold plating, and "18KJF" means 18K imitation gold. At present, some merchants dealing in 18K gold jewelry take advantage of the weakness that the masses don't understand this common sense, and set the price of gold-plated or imitation gold jewelry to be the same as or even higher than that of gold jewelry with the fineness of 18K. Customers don't explain to customers when buying, which makes customers mistakenly think that the jewelry marked with "18KJP" or "18KJF" is 18K gold jewelry.
Therefore, I hope that consumers should ask more questions, know more, observe more and compare more when buying such ornaments, and beware of being deceived. Try to buy from famous shops and reputable stores.
Knowing 4C to buy diamonds increases confidence.
Carat weight
Big diamonds are precious and small diamonds are brilliant.
The weight of diamonds is measured in carats (also called cards). 1 carat = 200mg = 0.2g A carat is divided into one hundred parts, and each part is called one point. 0.75 carat is also called 75 cents, and 0.02 carat is 2 cents. Other things being similar, with the increase of diamond weight, its value increases geometrically; Diamonds with the same weight will have different values due to different colors, cleanliness and cutting. You can find high quality diamonds in every different size and shape. The most important thing is to find a diamond with the right size and style that you like.
Clarity (clarity)
Crystal clear and pure beauty is hard to find.
Diamonds are crystallized from mantle magma deep in the earth, with complex environment, diverse components and extremely high temperature and pressure. After hundreds of millions of years of geological changes, they inevitably contain various impurities or defects. The color, quantity, size and location distribution of these inclusions have different degrees of influence on the clarity of diamonds.
Generally, the internal and surface defects of diamonds and their influence on the brilliance are analyzed with a magnifying glass with a magnification of 10. The clarity grades of diamonds without diamonds are subdivided into LC, VVS 1, VVS2, SI 1, SI2, P 1, P2, P3 * * * 65438. There are five grades of defective diamonds: excellent, very good, good and relatively good.
Color (color)
Colorless, elegant and rare.
Diamonds have a variety of natural colors, from precious colorless (white after cutting), rare dark blue and pink to common pale yellow. The more transparent and colorless, the more white light can penetrate and become more colorful after refraction and dispersion.
The grading of diamond color is determined by technicians repeatedly comparing the diamond to be graded with the standard color colorimetric stone in the grading environment of professional laboratories.
The whitest diamond is classified as D (starting from the first letter of the diamond). The color of diamonds is divided into 1 1 grades, which are D, E, F, G, H, I, J, K, L, M and N in turn.
Cut (cut)
Exquisite carving and shining
The brilliance of diamond is attributed to its unique high refractive index and high dispersion. However, uncut diamonds are just plain in appearance. Only through accurate calculation, careful design and perfect cutting and polishing can light be fully reflected from the top surface and beautiful diamonds shine. Diamond is the hardest substance. It is indestructible and never wears away. Once it is cut and ground, it will shine forever.
The way to judge the quality of cutting is to pick up the diamond and stare at the jumping light on it. The exquisite diamonds of lathe are dazzling and will not be lost because of inlay or different styles. Simple, right? You can do it too. The level of lathe work is divided into: very good, very good and average.
How to buy real jade
First, we must first learn the basic knowledge about jade; Second, choose a reputable old shop to buy jade; Third, shop around; Fourth, ask whether it is goods A or B; Fifth, ask the store for the appraisal certificate, especially the certificate issued by the Guangdong Provincial Bureau of Technical Supervision and other authoritative departments. It was done at 5 o'clock above. Even if you can't buy cheap goods, you can buy genuine products to avoid economic and spiritual losses.
Are South African Diamonds produced in South Africa?
At present, diamond deposits have been discovered in 27 countries in the world, most of which are located in South Africa, the former Soviet Union, Australia and Canada. China also found a few diamond mines in Wafangdian, Liaoning, Mengyang, Shandong and Shui Yuan, Hunan. In Africa, Angola, Botswana, Zaire, Tanzania, Guinea, etc. They are all important raw diamonds. South Africa is the first country in the world to discover the large-scale use of diamonds. This country produces many famous big diamonds and high-quality diamonds, which makes "South African Diamonds" very famous. Due to commercial factors, the crude diamond output of various countries has not been announced recently. Generally, the top five diamond producing countries are Australia, South Africa, the former Soviet Union, Zaire and Botswana, while the output ranking is: Australia, Botswana and the former Soviet Union and South Africa are the least.
The least cutting (machining) center is not in the diamond producing area. The main diamond cutting centers in the world are Belgian, Antwerp, new york and Indian, and the cutting centers are far away from the mineral producing areas. The processing and sales of diamonds are like this. British company De Beers controls more than 80% of the world's rough diamonds. The rough diamonds mined by the company are sold to the processing center through the Central Sales Organization (CSO) and then further sold. Therefore, the market supply and price of diamonds are monopolized, which makes their prices rise every year. The chemical properties of diamond raw materials from the same origin have not changed. There are diamonds of different quality in each mining area. Diamonds are graded according to 4C standard, not according to the place of origin. It is almost impossible to confirm the origin of diamonds. Just like this, the country's usual identification certificate does not indicate the place of origin. We often see that the most authoritative GIA certificate in China does not contain the content of the place of origin, nor does it issue the name of the place of origin. Based on the above factors, China promulgated 1996, and on 1 May 19971day, the national standard clearly stipulated that "the place of origin does not participate in naming", and specifically pointed out that diamonds cannot be called "South African diamonds".
Why do "South African Diamonds" often appear? On the one hand, diamonds were first discovered in South Africa, and many famous diamonds are produced in South Africa, which is a traditional title. Secondly, in the 1970s, the Soviet Union produced a kind of diamond imitation "artificial cubic zirconia" (commonly known as "Soviet diamond", which looks like a diamond) with commercial value. In order to distinguish it, people generally call natural diamonds "South African diamonds". In addition, influenced by Hong Kong, jewelry stores in Hong Kong call diamonds "South African diamonds", which is purely a commercial act. It is not rigorous and standardized, and the national standards in the mainland are not allowed.
Look at the jade and argue the fake.
Real jade is moist and shiny, translucent and opaque, and it is normal to have cotton wool or other impurities in jade. Fake jade has no aura, its color is dry and dull, and some have bubbles in it.
The real jade feels heavy in your hand, but the fake jade floats lightly. Real jade is hard, leaving no trace when cut with a knife, while fake jade is soft, leaving traces when cut with a knife.
Hang the appraiser in the air with a thread and pat him gently. Zhen Yu's voice is crisp and pleasant, soothing and far-reaching. False but not beautiful (this method is suitable for slightly thinner jade pendants).
Real jade has uneven fracture and dense material structure. The false fracture is neat and shiny, and it is a glass thing; The fracture material has a rough structure and no waxy luster. Observe carefully with a magnifying glass more than seven times, identify its edges and corners, holes, depressions and scribe lines, and you can find the clues of counterfeit goods in subtle places. gold
Gold is a precious metal with lasting luster. Its texture is soft and can be refined into various shapes.
6? Physical properties of 1
6? 1 density:
6? 1 Appearance: golden yellow
6? 1 melting point:
6? 1 hardness:
6? 1 Scalability: Excellent
1 9.3g per cubic centimeter 1064 degrees Celsius 2.5 mohs (similar to human nails) -( 1 g of pure gold can be drawn into filaments1km long, so it is the first choice for jewelry).
6? Chemical properties of 1: it does not oxidize at room temperature, and is insoluble in acid (soluble in aqua regia) HG)G999 or pure gold). The gold content is not less than 999‰.
6? 1 afraid of mercury (Gong
Common classification of gold in the market
6? 1 thousands of gold (seal:
6? 1 quanjin
6? 1 18K
6? The modern seals of 1 are generally in Chinese.
platinum
6? 1 physical properties: density:
6? 1 hardness: Mohs hardness
6? 1 chemical properties: stable, insoluble in any acid at room temperature.
Classification of common platinum in the market
6? 1 PT990
6? 1 K platinum platinum: the English full name of platinum is karat white Gold, and the Chinese literal translation is "platinum". It is made of gold as the main component, plus silver, copper and a small amount of nickel and zinc, and does not contain any platinum. Their main chemical compositions are completely different. We can't simply think that K gold contains 75% platinum.
K
6? 1 18K gold and 18K platinum: 75% gold. However, due to the different proportions of other 25% metal components, the appearance colors of the two are different, with K gold slightly lighter and yellow in the middle.
They are both.
6? 1 18K gold and 18K gold-clad and gold-plated are alloy jewelry containing 75% gold, while 18K gold-clad and gold-plated jewelry is only wrapped or plated with a thin layer of 18K gold on the surface of jewelry made of copper or other metals, and its mark is usually "/kloc". Bags and gold-plated jewelry will fade into completely different colors in a short time, which is essentially different from 18K gold. S990, S925 and S800. S990 jewelry is also called foot silver jewelry, and the silver content is not less than 990‰. The silver content of S925 jewelry is not less than 925‰. The silver content of S800 jewelry is not less than 800‰.
18K
silver
6? The chemical element of 1 is silver, a silvery white precious metal with low hardness. Common silver ornaments on the market are
6? 1 silver jewelry material and content imprint, such as
6? 1 Our silverware school "Genimanu" is in full compliance with international standards.
palladium (Pd)
Inlaid jewelry
6? 1 The cut and polished diamonds are sent to the jewelry factory. The jewelry designer designs the drawings, mounts them, polishes them, casts them, and then sets them by skilled workers to fully show the brilliance and beauty of the diamonds. There are four common mosaic methods:
6? 1 pointed inlay method: this is the most common inlay method, which is mainly composed of several metal columns. Make a 7-shaped notch above the metal claw, put the waist of the diamond into the notch, and then press the diamond on the claw with pliers to fix the diamond.
6? 1 groove setting method: use a metal wall with pits on both sides to put the diamond into the pit, and then press with pliers to fix the diamond.
6? 1 edging inlay method: firstly, make a cylindrical inlay, make a pit on the wall of the inner cylinder, put a diamond with a suitable size in it, and then press the metal edge on the petal surface of the diamond waist to fix the diamond.
6? 1 nailing method: punch a small hole in a piece of metal, then put the diamond in a fixed position, push the metal up and forward with a shovel to form a small nail, cover it on the diamond and put it on.
925 pure silver diamond inlay method S925 indicates that its silver content is not less than 925% 2 1.45g per cubic centimeter, which is the highest among metals. Appearance is silvery white, melting point: 1769 degrees Celsius 4.3 (harder than gold), good ductility (all platinum), and its platinum content is not less than 990 ‰; The platinum content of PT950 jewelry is not less than 950 ‰; The platinum content of PT900 jewelry is not less than 900 ‰; The platinum content of PT850 jewelry is not less than 850 ‰; Among them, the gold content of PT950 as long gold (imprint: G750, Au750 or 18K) is not less than 750‰/ yellow foot (imprint: G990 or pure gold) and not less than 990‰.
good luck