How to identify copper coins

Method of identifying counterfeit money

(1) traditional identification method

(1) Distinguished words:

China's currency culture has a history of thousands of years since its emergence, evolution and development. Writing is a tool for cultural exchange. In China, when metal coins are produced, characters are cast on the surface of the currency, which indicate the value of the currency, the place name or the name of the coin. Coins without words are relatively rare. Coin Qian Wen of different times has its own style and charm. Although future generations can learn from their predecessors, it is an imitation after all, and at best it can only reach a vivid level. Due to the differences in gestures, strokes and strength, it is impossible to be completely consistent. In this way, it is a very important aspect to identify the characters on ancient coins. Here, we can cite some typical characteristics of coins in different times to illustrate.

The pre-Qin period is the historical period of the emergence and development of China's currency. During the Spring and Autumn Period and the Warring States Period, due to the great development of social commodity economy and the establishment of monetary economy, metal coins began to enter the historical stage. The coins in this period mainly include knife coins, cloth coins, coins and Chu coins. No matter which series of coins, most of them are cast with characters, and their general characteristics are thin, smooth, ostentatious and random layout. As the pre-Qin coinage characters were directly engraved on Qian Fan with a knife, the characters left an obvious meaning of carving with a knife, and they were written in one go without any trace of rewriting. At that time, because the coinage characters were made by coinage craftsmen, the characters were not as neat and rigorous as the inscriptions on contemporary bronze containers, and the layout was relatively extensive, but they were coherent and vivid. Word-making in the pre-Qin period has these characteristics of the times, and even an expert who has studied it is difficult to achieve the degree of ecstasy and indifference, not to mention that forgers are mostly snobs.

It is rare to print Wang Mang's coins with a unique hanging needle, except for the living spring, Daquan 50, Huobu and Dabu Huang Qian. Therefore, there are many fakes that survive, and some even exceed the number of genuine products that survive. Usually there are three kinds of fakes of Wang Mang's money: cloth, big cloth and yellow money, and flat money. It is also called the wrong knife and Jin Cuodao. The real "knife" is gold embedded in the meat of the ring head, while the counterfeit money is either not a "knife" or a "knife" is in Yang Wen. It is said that the word "one knife" is described by gold powder, and the forgery method is relatively easy to identify: although there are many surviving and archaeological discoveries, the cloth surface and the cloth surface are yellow. As far as calligraphy is concerned, Qian Wen, who is rich and colorful, can best reflect the verve and level of Wang Mang and Qian Wen. It is slender and powerful, smooth and beautiful, and the layout is decent and perfect. Authentic products are generally spicy and sharp, and the general method of counterfeiting is to use genuine imitation. Although the forged product looks the same as the genuine product, it lacks the original vitality and looks unremarkable. In addition, there are still some defects in manufacturing and processing.

The recognition of coin Qian Wen did not happen overnight. It is necessary to experience and chew by touching a large number of physical objects, so that it is possible to understand and master the calligraphy characteristics and styles of Qian Wen, each coin in each era. In addition, it is best to have good calligraphy artistic accomplishment and appreciation ability.

(2) Identification of rust:

Identifying rust is another important aspect of identifying the authenticity of coins.

Distinguishing rust means distinguishing the rust color of copper, which generally refers to copper rust. Copper rust refers to a layer of oxide formed on the surface of copper coins due to the age of casting. Due to different geographical, geological and burial conditions, the accumulation degree of this oxide is also different. This kind of fine or massive copper rust is hard and firm, and it emanates from the copper tire itself on the surface of the money body. It is generally called "natural rust" or "hard rust". It is difficult to remove with nails or knives, and the distribution is natural and appropriate. Due to the different chemical elements contained in the soil layer, the colors of copper rust are different, mainly green, red and blue.

To distinguish rust, we must first know some fake methods of fake rust, otherwise, true and false, false and true are confused. According to past experience, we summarize the main methods of making fake rust as follows:

A. Pigment and pigment mixed on counterfeit money can almost be true, but it is easy to fall off after a long time.

B rosin or glue mixed with pigment to make fake rust is not as effective as the first method.

C. Put counterfeit money in wet soil or semi-wet place and let it rust naturally. This fake method takes a long time and produces more real effects than the first two, but it is easy to fall off once it is rubbed.

D, soaking counterfeit money in vinegar, and adding copper sulfate to form green rust with crystals.

E. If counterfeit money is soaked in sulfuric acid solution, it will rust quickly, but the surface of money is seriously damaged.

F, mixing the patina with adhesive and acid solution, and smearing it on counterfeit money for forgery. The fake rust produced by this method is firm and true in color, but it lacks expressiveness and is easy to be fooled.

Knowing the fake method of fake rust is of great benefit to us in identifying the authenticity of copper rust. No matter what method is used to make fake rust, its common feature is crisp texture. Because most of them are not naturally produced in copper tires, they are produced through chemical reactions, so they generally float on the surface of money and can be easily removed by fingernail or knife cutting, so they are also called "floating rust" or "powder rust". Because real rust is naturally formed, its distribution is casual and decent, without affectation, while fake rust is not. Because it needs to be realistic and can be confused with the real thing, counterfeiters often deliberately ponder the distribution of copper rust, and finally show clues.

In coins found in southern China, especially in Anhui, Jiangsu and other places, real copper rust similar to powdery rust will also be formed on the surface of coins. Ancient coins with this kind of copper rust can't be uniformly classified as fakes. The difference between the two is that the copper rust similar to powdery rust produced by real coins does not float on the surface of coins like fake rust, but naturally radiates from copper tires. Therefore, it is not easy to be eliminated when it is connected with coins. When identifying the authenticity of coins, we should know as much as possible about the origin, discovery place or land of the coins.

It should be pointed out that not all coins have copper rust on their surfaces, such as the gold plate of Chu in the pre-Qin period. Although it is nearly two thousand years from today, its color is still shining. Identification of these things, only by rust color, will get nothing, at a loss, which needs to be combined with text and production technology at that time to analyze and judge. The same method is also used to identify rustless Qing coins.

Coins are generally divided into "raw pits" and "cooked pits". Pit refers to newly unearthed coins, the surface of which is generally seriously oxidized. Cooked pits are handed down from ancient times that have not been buried. After a long period of circulation and touching, the coins in the cooked pit naturally form a brown or dark brown protective film on the surface of the coins. This protective film is commonly known as "patina". Although it is a very thin layer, it will not fall off when boiled in water. Forging patina is generally blackened on lampblack and lampblack, and then waxed and polished. If washed with water, it basically disappears. Another is to put coins in places where melanin is concentrated, such as coal piles. After a long time, a thin black coating will be formed on the surface of coins, which will look like patina after polishing. This should be paid special attention to. The common patina is a dark brown antique handed down from ancient times, also known as "black lacquer antique". There are two common methods to forge ancient colors handed down from ancient times: one is to burn fake money with fire, take it out and cool it to make the surface of the money black, and then put it in your pocket. After a year and a half, the color will be very smooth, similar to real money; Or after the horn is roasted and cooled, wipe the money with grease on the cloth. This method occasionally has red rust. Second, counterfeit money is soaked in hydrochloric acid or sulfuric acid for a day or two, and turns black after being taken out. Processed by the former method, the color is the same as the real one. This kind of fake money handed down from ancient times should be carefully identified according to the characters, shapes and production, in addition to the method of identifying the true and false.

(3) shape recognition system:

The form of coins is generally stipulated by the government. The shape includes the diameter of money, the size of money, the thickness of money body, the width of inner and outer Guo, the depth of money back and so on. Because metal coins were produced in the Spring and Autumn Period and the Warring States Period in China, the shapes of coins in different times are not exactly the same, some are similar, and some are very different. Being familiar with the shape changes of coins in past dynasties is also an important aspect to identify the authenticity of coins.

Generally speaking, the shape of coins in China has undergone three major changes: first, imitation of production tools and household utensils; Second, a round coin with a square hole; Third, round coins without square holes, such as silver and copper.

Although there were many forms of coins in the pre-Qin period, we can still sort out several main clues. Pre-Qin currency can be divided into four series: coins, knife coins, map coins and Chu coins. Cloth coins are made of imitation bronze farm tools. The main difference between various cloth coins is that the head, shoulders and feet are generally light and thin. Knife coins are cut by imitation bronze tools, and their shapes are basically similar. Qi Dao is big and heavy, Ming Dao and Round Dao are light and thin. Generally speaking, round coins are flat-backed. The square hole coins cast by Qi and Yan have Guo, but the round hole coins in Sanjin area do not. It is said that they are all made of imitation jade walls. Chu ant nose money comes from imitating natural shellfish, and gold plate comes from imitating turtle back. The pre-Qin monetary form is unique in the monetary history of China, which is quite different from other monetary forms in previous dynasties.

Since the Qin, Han and Six Dynasties, China's currency has been standardized and unified, generally in the shape of square holes and round money. The shape of this square hole round money continued until the early years of the Republic of China, lasting for more than 2,000 years. During the Qin, Han and Six Dynasties, half-taels of money were generally flat-backed, except for the early four-taels, which were a little big and heavy. A Qin's half-weight 64 grams collected by Shanghai Museum. The later period is small and frivolous. Five years after Emperor Yuan Shou of the Han Dynasty (1 18 BC), five coins were generally deep and narrow. The Yong Tong Wan Guo and Wu Xing Da Bu, which were cast in the Six Dynasties, are similar in shape, although they are different in size. In the coins of the Sui, Tang and Five Dynasties, there was a wide edge.

Coins in the Song Dynasty were changed from the previous system. The back of money was flat and shallow, and most foreign coins were wide. Like coins minted in Song Huizong, coins in the Jin Dynasty are very exquisite, with deep backs and clear outlines. The same is true of yuan and Ming coins. The coins of the Qing Dynasty restored some features of the Song Dynasty. The difference is that the inside and outside of the coin are relatively simple. Before Daoguang, coins were first class, and after Xianfeng, big money appeared.

Although round coins with square holes are still cast, machine-cast coins mainly made of silver coins and copper coins have appeared since Guangxu in the Qing Dynasty, and machine-cast nickel coins and aluminum coins have appeared in the Republic of China. During Guangxu period, a number of square-hole round coins were minted, which were mostly found in Baozhe Bureau.

④ Identification and production:

Understanding the coin casting technology of each era is an important aspect for the identification of coins.

In China, the model casting method was adopted before the Tang Dynasty, and the mother money casting method was adopted after the Tang Dynasty. Before the Tang Dynasty, there were several kinds of textures in Qian Fan, such as clay fan, stone fan and copper fan, which were not used at the same time. How much a fan can be cast also experienced a development process. The earliest clay pottery model appeared. At first, it was a model of casting a dollar. Stone models and bronze models were used during the Warring States period. Usually two coins are cast in a model, that is, two coin cavities are carved in a model. But the number of knives and coins that a stone fan can cast is not limited to these, usually three to five. As far as stone mold casting technology is concerned, the coin surface adopts stone mold and the back adopts clay mold, which solves the thermal deformation problem of the mold body. At present, the use of copper coins in the pre-Qin era is only seen in Qi Dao and Ant Nose Money. Although there are copper molds for distributing coins in previous records, there are no physical objects. Qi Li copper mold coinage adopts vertical stacking casting technology, which is not directly used for coinage, and the clay mold still needs to be turned during coinage. At that time, it was directly cast with ant nose copper coin model. It is said that only five copper models of ant nose coins have been found so far, of which two pieces selected by Anhui Fanchang County Cultural Relics Group 1982 in February are quite exquisite and complete, and 66 pieces and 67 pieces can be cast at one time respectively. During the Qin, Han and Six Dynasties, clay models, stone models and bronze models were used at the same time, and the number of coins increased greatly. 1986 A half-coin model of elm pods found in Xiancheng Village, Boxing County, Shandong Province, can cast 176 coins at a time, which is really rare.

During the Sui and Tang Dynasties, the amount of minted money increased greatly, but no tools like Qian Fan were found. There is a treasure note in the Tang Dynasty in Shanghai Museum, which was identified as mother money, indicating that the casting technology of mother money casting method had been used at that time, which directly affected the coin casting technology of later generations. According to the records in Tiangong of the Song Dynasty in the Ming Dynasty, we learned the general process of casting money from ancient mother money by turning sand: using four pieces of wood to empty the box, filling the middle, putting some mother money on it, and then closing the same box on it, that is, the back of the money, thus completing dozens of boxes, with gates left on them, tied tightly with ropes, poured with molten copper inside, and opened the box after cooling, thus forming branch-shaped money. Here, the mother money actually acts as a monetary model, which is made of copper and tin in advance and distributed by the central government to all localities, and all localities turn sand into money accordingly. The mother money has a carved mother on it. The so-called carving mother is a coin pattern carved and processed artificially on a copper blank. The earliest surviving engraving mother is Jiajing Bao Tong in Ming Dynasty, which is collected in Nanjing Museum. Below the mother money is a sample coin, which was cast by turning sand with the mother money, and it was a sample coin before a large number of circulating coins were officially cast. There are two kinds of sample money in Qing dynasty: one is the sample money issued by the Ministry, and the other is the sample money given away. As for the technological process of casting with mother money, it is also recorded in Zhang Shinan's travels: the order of employing people is "sand mold", "grinding money" and finally "arrangement".

Although the mother money casting method was widely used in China after Sui and Tang Dynasties, there were exceptions. As far as we know, during the Five Dynasties and Ten Kingdoms period, Wang used the model casting method to cast the "Yonglong" statue. A few years ago, a model of Tongzhibao was found in Beijing, indicating that money was occasionally used when casting money in the Qing Dynasty.

After a basic understanding of the general situation of coinage technology in various historical stages in China, we can make a clear comparison by looking back at the production level of counterfeit money.

(2) Modern scientific and technological appraisal methods

In China, copper coins are basically made of bronze, and coins made of brass began to appear in the late Ming Dynasty. The chemical composition of copper coins cast in each era is different. Zhou Li Kao Gong Ji recorded the proportion of bronze alloy composition in the Spring and Autumn Period and the Warring States Period. This provides another kind of information for us to identify the authenticity of coins today.

① Destructive chemical composition analysis:

The so-called destructive chemical composition analysis is to remove the copper rust on the surface of coins in a certain era, take some samples from the exposed real copper, and carry out chemical analysis on the proportions of various elements such as copper, tin and lead, and finally get the percentage of various chemical elements contained in various copper coins in this era. Using this method of chemical composition analysis, we can also identify the authenticity of coins. However, this destructive chemical composition analysis method has a fatal weakness, that is, it will damage coins, so we must be cautious in adopting this method, otherwise it is not a waste to analyze rare coins like this.

② Noninvasive component analysis:

The nondestructive component analysis method, like the destructive component analysis method, obtains the percentage of trace elements such as copper, tin and lead by analyzing the chemical composition of copper coins, finds a relatively stable value of the chemical element content of copper coins in this era, and uses it to identify whether it is the same copper coin made in the same era, thus obtaining the authenticity of the coins. This method is more advanced than the destructive method. It adopts proton X-ray fluorescence analysis method and draws a conclusion through computer calculation.

Whether it is destructive chemical composition analysis or non-destructive chemical composition analysis, in the final analysis, it is the texture of copper coins (of course, coins of other textures are also applicable). According to the different textures of copper coins, these methods are quite scientific to identify the authenticity of coins. However, in the actual identification process, we often encounter the problem that we need to make judgments immediately, but they take a lot of time, so they are not very practical, which requires us to observe colors with our own experience. As we know, copper is also divided into copper, bronze, brass and other textures. The copper colors of these copper coins with different textures are not exactly the same, even though their copper content is around 70%. So it is convenient for us to identify counterfeit money. For example, Xinjiang red money is made of copper, so the color is red. If there are brass Xinjiang coins (usually made of brass in Qing Dynasty), they are probably forged and should be taken seriously. In other words, to identify the authenticity of coins, we should also pay attention to the color of copper coins.

In addition to the chemical composition analysis methods mentioned above, the flaw detection of copper coins is especially suitable for the identification of counterfeit coins carved and inlaid.

In any case, identifying the authenticity is the basis for collecting and studying coins. If you don't know how to distinguish authenticity, you can't talk about collection and research. To identify the authenticity of coins, we need to contact a large number of physical objects, observe them carefully, gradually accumulate experience in practice, and constantly sum up a set of effective methods to eliminate the false and keep the true, so as to serve real life.

3. Basic knowledge needed to identify ancient coins.

Appraisal is the comprehensive knowledge of various related disciplines. Limited professional knowledge alone can't solve some problems, which requires us to have a broader knowledge structure.

To identify ancient coins, we must first be familiar with history, not only general history, but also dynastic history and special history, which is the basis of identification.

Secondly, we should be familiar with and master the history of money. The occurrence and development of money, like other historical events, have a historical process, and it is very important to understand such a process. Otherwise, many important issues such as the evolution of monetary system, currency circulation and casting will not be known.

Third, we must have knowledge of numerology. Coin minting is a subject that studies the occurrence and development of coins, as well as different versions, textures, shapes and casting characteristics of coins. In the history of China, coins can be divided into many different versions according to their thickness, size, Qian Wen and ornamentation, especially for coins in the Song Dynasty, the focus of people's research is the version. Coins are generally made of copper, iron, lead, gold and silver. Coins of one or more textures were forged in any dynasty, which is particularly important for identification. Moreover, the techniques used in minting coins in different historical periods in China are different. Generally speaking, the model casting method was used before the Tang Dynasty and the mother money casting method was used after the Tang Dynasty, that is, the technological process and technical level of these two coin casting methods were different in different times; So we need to know and master coins before we identify them.

Fourth, we should understand aesthetics, calligraphy and seal cutting, and have a certain accomplishment. When we talk about authentication, we often mention some words that are difficult to understand and abstract, such as the style, spirit and breath of words. Without knowledge of aesthetics, calligraphy and seal cutting, it is extremely difficult to understand and recognize these words. In addition, you should also have knowledge of linguistics, philology and philology. We often meet coins from China. Therefore, the knowledge of ancient Chinese and ancient philology is also very important for the identification of coins and cannot be ignored.

In a word, it is important to strengthen one's self-cultivation and temper in identifying coins. Only in this way can we master the trick of identifying the authenticity of coins.