Gold coins are mostly round and disc-shaped, which are expensive and now belong to precious collections. In ancient times, it was bought and sold as money. For a long time in human history, gold coins were the official currencies of many countries. In modern times, it is generally a private collection, which is commemorative and has high commemorative value.

Basic introduction Chinese name: gold coin mbth: gold; ? Gold coins; Shape: round or disc-shaped features: expensive modern function: ancient function Precious collection: currency application: introduction to buying and selling, classification, fame, value collection, collection significance, preservation, 12oz value, common sense, gold coin quality standard unit description: ounce classification: gold coins made of gold, with liquidity and investment value, also known as investment-type gold coins, such as common in China. Commemorative gold coin commemorative gold coin is also a kind of gold coin, which is usually printed and issued for a specific purpose or an event. The most famous gold coins traded in the gold market are: South African krugerrand, British British Gold and Silver Coin, Canadian Maple Leaf Gold Coin, American Eagle Gold Coin and Mexican Gold Peso. China's panda gold coins are also in international demand. There are also many kinds of gold coins in the United States, mainly the double eagle coin with the head of the Statue of Liberty printed on the back. The fineness is 90%, and the coin weighs 33.436 grams. The auction price of gold coins in the United States is very active, and the highest price is 1979. 1787 gold coin, worth $725000. Mexico's gold peso began with the currency reform in 1905. The early gold peso was cast in 1905- 193 1, and the later gold peso was cast in 1943 and 1953. Because * * * often casts new coins with old versions, it is difficult to determine the real casting age of a gold coin. The gold coin has a diameter of 37mm, a purity of 99.9%, and a weight of 41.66g. The front of the coin has an eagle pattern, and the back has a sign of victory of the Grey Checker Party. Gold coins The British Royal Gold Coin was minted earlier and was issued by King George III in 18 17. 1937- 1957 did not cast gold coins. Prior to this, gold coins of *** 1 1 were minted, most of which were marked by kings. After 1957, the pure gold coins were recast as *** 12 gold coins with the head of Queen Elizabeth II printed on the front. South African krugerrand has a casting history of one hundred years. The fineness is 22K or 9 1.62%, the coin weight is 1.09 oz, and the gold content is 1 oz. Gold coins were first issued in 1867, and the quantity was limited. 1870 began to export, and the coin has the head of former South African President Kruger on its surface. The gold leaf of Canadian maple leaf was cast in 1979 with a face value of $50. There were about 1 10,000 pieces at that time. The fineness is 99.9%, the diameter is 3 cm, and the thickness is 2.8 mm. The surface is the maple leaf logo, and the back is the head of Queen Elizabeth. Austrian krona gold coin, weighing 33.87g, with a diameter of 37mm and a purity of 98.02%, is also very popular internationally. Colombian 5 peso gold coin with the heads of Simon and Bo Levar and the portrait of the lottery worker. The 5 peso gold coin weighs 7.98 grams, with a fineness of 9 1.67%, and enjoys a high reputation in the field of international gold coin collection. There are many ways to identify the value of a gold coin in the value collection; For example, its rarity, manufacturing age, manufacturing conditions, and the number of unified styles produced are all determined, and even the bacteria on an ancient gold coin are not spared. Collecting gold coins is not only collecting gold coins issued in the same era, but also collecting official gold coins issued by ancient people. Often collectors attach great importance to those historical gold coins, because such gold coins are worth having for archaeologists. Every country will have a collection market for ancient gold coins, and collectors also need to pay attention to fake and shoddy gold coins. Maintenance of gold coins The order of antioxidant capacity of refined coins is gold, nickel, silver, brass and copper. The oxidation resistance of nickel exceeds that of silver, and copper is the most easily oxidized. Platinum, palladium and aluminum-magnesium alloys are not the mainstream of refined coins, so they do not need to be sorted. Gold in nature will not react chemically with oxygen and other gases in the air, because the purity of gold coins is not very pure, which contains a small amount of metal components such as silver, so trace oxides often appear on the surface of gold coins, mainly because sulfur in the air combines with silver in gold coins to generate trace sulfides. Metal oxidation is related to materials and storage. For example, some of the gold ornaments before 1000 years ago are glittering and some are stained, so it is meaningful to discuss the binding and storage methods of coins. As long as the precious metal coins are in good appearance, the impact of oxidation on their value should not be too great, so the oxidation of refined coins is not terrible, because the collection value of refined coins is not only reflected in aesthetics, but more importantly in the version, that is, whether refined coins and ordinary coins can distinguish two different versions after oxidation, and it is lack of basic knowledge of coin collection to expect to distinguish the version through different packaging. There is no chamfer on the edge of copper-nickel alloy refined coins, which has nothing to do with oxidation. The oxidation rate of the alloy itself is slow. Even if it is oxidized, it can be clearly distinguished from the surface of the coin. My Shenyang version and Pingnian refined coins are all oxidized to gray, but the value is basically unaffected. Steel core nickel-plated refined coins are kept normally. I estimate that there will be no obvious oxidation in 100, so the issue of oxidation need not be discussed. Brass alloy is only used for ordinary commemorative coins from 0 1. Because ordinary coins have better technology, both sandblasting and polishing, there is not much difference between refined and ordinary coins. If it is oxidized, the difference between coins will be smaller. The difference between coins is divided into two situations: one is that the zodiac has the letter "J", and the other is that there is no difference in other varieties, including Olympic commemorative coins. There is no sandblasting on ordinary coins of copper alloy gold coins, which has obvious visual difference with refined coins, but the difference will become smaller after oxidation, and there is no difference on the edge of coins. There are many factors that affect the collection value of refined coins. For collectors, it is necessary to collect them comprehensively and systematically, without which any variety is incomplete. Collection Significance The series of activities of popularizing gold coin knowledge among middle school students carried out by China Gold Coin Corporation is not only conducive to popularizing the basic knowledge of precious metal commemorative coins in China to middle school students, but also conducive to promoting the excellent monetary culture of gold coins in China and inspiring people's patriotic enthusiasm. It is also a good way to fundamentally prevent and solve people's damage caused by buying fakes. Giving lectures to teachers and students, letting students visit the exhibition room of precious metal commemorative coins in China, and getting close contact with glittering gold and silver coins is far more vivid than the way of book teaching. The best way to remember is image, which is both profound and easy to remember. Therefore, the teachers and students of Huaxia Girls' Middle School have learned a lot about precious metals through lectures and visits, so as to master and understand the consciousness and methods of collecting coins from their student days. Try not to touch the surface of gold coins directly with your hands, because sweat stains on your hands will pollute the surface of gold coins. It is best to seal the gold coins with sealing plastic, which is more convenient to watch and can also prevent the dust in the air from polluting the surface of the gold coins. Try not to collide, because it is easy to leave traces when colliding with each other. If the gold coin is dirty, it should be slightly washed in warm soapy water, then washed with clear water and gently dried with a soft cloth, and finally placed in a dry and ventilated place; Try not to rinse with very alkaline water or brush with a brush. Alkalinity can easily corrode the surface of gold coins. Color-changing silicone rubber should be placed in the place where gold coins are stored, which mainly plays the role of moisture absorption; Silica gel is blue when it is dry and turns red when it absorbs water. It's best to put it in an anti-corrosion and moisture-proof safe. 12oz value

12oz gold coin plate is a historical plate of new China gold and silver coins, and only 22 varieties have been released, namely 1984 ~ 1995 panda gold coin (*** 10) and 1988 ~ 65438+. Panda Gold Coin In the early days, the new China gold and silver coins were mainly exported to earn foreign exchange, so they attracted foreign customers as much as possible in terms of quantity and specifications: "120oz gold coins have a diameter of 70mm, which is larger than 5oz gold coins, but smaller than 2oz and 1kg gold coins, which is unique in appreciation. However, the production of 12oz gold coins requires special embryo cakes, and the number of gold and silver coins issued is very small. Therefore, after the gold and silver coins are mainly exported to domestic sales, there is no trace of 12oz gold coins in the domestic mainstream gold coins. " In the "big family" of 12oz panda gold coins, from 1984 to 1995, 10 panda gold coins were issued one after another. Except for 1986, 1987, 1988 and 1990, all the panda gold coins of other years are top treasures. It is reported that the coin edge of this set of 12oz panda gold coins is worth studying: the version of 12oz Golden Cat 1984 has a bare edge, but due to the small circulation, its coin edge has a manual number. The nominal circulation of 1986, 1987, 1988, 1990 and10/is relatively large, so these 12oz golden cats are all toothless. The circulation of 12oz Golden Cat 1992 version is only 99 pieces, but it is also full-toothed, and there is no manual numbering. 1992 12oz golden cat and 1992 version 5oz gold are the only 99 gold coins in new China. 1993, 1994 and 19, 95, 12oz Golden Cats all have 10 mm or more smooth-edged tooth slots on the whole tooth edge for manual numbering. In other words, the ordinary panda gold coins of 1993 12oz should be numbered next to the coins. The sample coins of 1993 12oz taken this time are full teeth (continuous straight teeth). The root of the current situation is called orphan. Common sense denomination: modern gold and silver coins issued by the state are legal tender, but their denominations are only symbols of legal tender, and they are not decoupled from the equivalent face value of gold or silver, and the face value is decoupled from the actual price. Because the gold and silver materials used in modern gold and silver coins fluctuate with the international price, the price of gold and silver coins is calculated by the international floating price of gold and silver plus processing fees and profit premium. Premium: When gold and silver coins are sold, the principal and silver are determined according to the gold price, while the processing fee and profit become premium, including all casting costs, storage and transportation costs, publicity and promotion costs, hedging costs, operating costs and appropriate profits. Color: There is no pure gold, there is no absolute pure gold in gold, there are always some other ingredients. The purity of gold is expressed by fineness, one is percentage and the other is K standard method. Gold and silver coins generally use percentages. Circulation: All kinds of commemorative gold and silver coins, whether sets or pieces, have a fixed number of issues, and the number of issues is limited and cannot be changed at will. The circulation of non-commemorative gold and silver coins is not restricted, and it is generally based on the sales volume at the end of the year. Ounce: the international name for the weight of gold and silver coins, with an ounce of 28.35 grams. Troy ounce: A unit of weight. The overall abbreviation is oz. Tr (UK) and oz.t (USA). Common in the measurement of precious metals such as gold and silver. 1 ounce = 31.1035g "ounce" is the international unit of gold measurement. One ounce is equivalent to the old weights and measures in China (16 is one catty). Under the old system, the gold collected by banks should be put into storage according to 1 (the old system), which means that the old system 1 is a little more than 1 ounce. Under the new weights and measures system implemented today, 1 ounce is equal to 31.1039g, which is equal to 0.622 taels per thousand restraint. Constant ounce: a unit of weight. The overall abbreviation is oz.av 1 oz = 28.350g 1 oz = 16 dram) 16 oz = 1 lb. Drug balance oz: weight unit, and the overall abbreviation is ap oz. 1 oz = 31.1030g.