Systematic classification of gold jewelry

1. Pure gold jewelry Pure gold jewelry is golden yellow, bright but soft, hardness 2.5, density 19.32g/cm3 (20℃), melting point 1064℃, good ductility, one gram of pure gold can be drawn into 2500 meters Long filaments, hammered into 9.6 square feet of gold leaf. According to international regulations, all pure gold jewelry is golden yellow, bright but soft, with a hardness of 2.5, a density of 19.32g/cm3 (20°C), and a melting point of 1064°C. It has good ductility, one gram Pure gold can be drawn into 2500 meters long filaments and hammered into 9.6 square feet of gold leaf. According to international regulations, all jewelry made of precious metals must have a mark on the inside of the jewelry, and the mark is required to indicate the gold content and the manufacturer. All gold content of 99% is called pure gold, and the content of 99.9% is called pure gold. Both pure gold and thousand pure gold belong to the category of pure gold. 2. K gold jewelry K gold refers to the alloy of gold and other metals smelted together. Because the English word for alloy is karat gold, it is called k gold for short. According to the amount of metal added in jewelry, the gold content in karat gold is also different. 24k refers to pure gold. If pure gold is divided into 24 parts, then 1 part is 1k, and the gold content of 1k is 4.1667 %, if it is 18k, the gold content is 18x4.1667%u003d75%. (1) K gold jewelry of yellow series K gold jewelry of yellow series (abbreviated as K yellow) is an alloy of gold, silver and copper. According to the content of gold, it can be made into k gold jewelry of different k numbers, mainly 22k, 18k, 14k, 10k and 8k. Asians like high-k gold jewelry, such as 22k and 18k, while Europeans and Americans like 14k and 10k gold jewelry. The color depth of the yellow gold series jewelry is related to the content of gold in the gold and the ratio of silver to copper. The color of 18k gold is yellower than that of 14k and 10k gold jewelry. For gold jewelry of the same number, if silver is more yellow than copper, it is lighter, and if copper is more yellow than silver, it is darker. (2) White series of karat gold jewelry White karat gold series of gold jewelry (abbreviated as k white), is slightly bluish white, and the imprints are marked with the wg mark. According to the combination, it can be divided into the following two types: The first type is gold The alloy mainly combined with silver, nickel, and zinc is called k platinum in the business world. 18k gold is a combination of 75% gold and 25% silver, nickel, and zinc. 14k white gold is an alloy composed of 58.5% gold and 41.5% silver, nickel, and zinc. The second type is based on gold and palladium, plus an alloy composed of copper, nickel, and zinc. It is based on the share of each metal in k gold as the basis for the title in the world. At present, there are only two varieties. That is, 334k white gold is a k white gold composed of 3 parts of palladium and 4 parts of copper, nickel, and zinc, and 226k white gold is a k white gold composed of 2 parts of gold, 2 parts of palladium and 6 parts of copper, nickel, and zinc. (3) K gold jewelry of the red series The k gold jewelry of the red series is mainly gold and copper, with a small amount of silver alloy added, and the color is light red. (4) K gold jewelry of the color series K gold jewelry of the color series of K gold jewelry is made by pressing different colors of K gold into thin slices, arranging them in opposite directions according to the colors, and forming the thin slices together by forging. 3. Gold-coated jewelry (1) Gold-plated jewelry Gold-plated jewelry is a layer of gold plated on the surface of the jewelry with copper as a blank by electroplating, but the coating is generally very thin, about 3-5um. (2) Gold-clad jewelry is also called gold-filled in the United States. Gold-clad jewelry is a layer of gold foil pressed on copper or silver sheet. The thickness of the gold foil is between 10-50um. Because the thickness of gold-clad jewelry is thicker than gold plating, its appearance is similar to that of gold jewelry. This kind of gold-clad jewelry is marked with kf in the United States. If the gold leaf is 18k gold, the 18kf mark is marked on the inside of the jewelry. (3) Gilt jewellery Gilt is an ancient gold-plating process, in which a layer of gold and mercury mixed thick paste is evenly coated on copper, silver and other low-value jewelry, and then baked at a low temperature. When it evaporates when heated, the gold adheres to the surface of the copper, then it is flattened and polished. 4. Imitation gold jewelry (1) Copper jewelry Copper jewelry mainly includes: red copper jewelry contains 85% copper and 15% zinc; brass jewelry contains 55-85% copper and 15-45% zinc; bronze jewelry contains 80-95% copper , 5-20% tin. (2) Copper-plated jewelry Copper-plated jewelry uses copper as a blank. The surface is plated with a layer of pure copper. Because the plating spreads on the surface evenly and smoothly, the color is beautiful, but its characteristics are exactly the same as copper jewelry. (3) Rare gold jewelry Rare gold jewelry is an alloy smelted by adding rare earth elements (lanthanum, cerium, samarium, magma, magma) to brass. (4) Titanium jewelry now has a titanium plating process, which is to burn pure titanium pieces in nitrogen and acetylene gas. At this time, if copper and other alloys are put into it, a layer of golden titanium nitride film can be attached to the surface , The thickness of the film is generally 1-2um. Previous: Gold may not always shine Next: Pure gold jewelry signs should not be written as 24K