is first. Among the 1995 auctions of Duoyunxuan in Shanghai is a copper stove (19.2 cm high), whose color can match the color of Buddhist scripture paper. In addition, some gold-sprinkled or gold-inlaid copper furnaces manufactured using special techniques are several times more valuable than ordinary copper furnaces.

The second thing is to look at the shape, caster, size and weight

The shape should be quaint and thick. Those with ears and feet are better than those without ears and feet. The finer the casters, the better. In terms of size, furnaces with a diameter of 8-12 cm are the most common and are small; furnaces with a diameter of about 15 cm are medium-sized, with fewer quantities than small ones, but are more valuable than small ones; and furnaces with a diameter greater than 20 cm are medium-sized. Large size, rare in craftsmanship, and very valuable. In the case of the same size, the heavier the furnace, the higher the value. For example, the Xuan furnace from the late Ming and early Qing dynasties collected by friends has a diameter of only 15.8 centimeters and a weight of up to 7 kilograms. It is a super heavyweight among copper furnaces of this size, and its value is several times higher than the ordinary one weighing 3 kilograms.

Finally, look at the quality of the model

The more refined and unique the model, the better it will be for dating, and the higher the value of the copper furnace. Xuande furnaces were cast in the Ming, Qing and Republic of China, but how to determine the age? In terms of overall shape, the overall style of the Ming Dynasty copper furnace is elegant and vigorous. By the late Ming and early Qing dynasties, copper furnaces were still robust, but not as elegant as the earlier ones. By the 18th century, the style began to become more delicate, striving for changes in shape and decoration. Some were elegant, but overall they lacked richness. The two pictures below are from the author's collection. They were originally sold at Christie's in London. They are 31.8 cm high. They are from the Qianlong period and the Qianlong period. The decoration is more complex and the coral inlay is intact. In the 19th century and after, the quality of copper furnace castings deteriorated, and both the patina and decorative shapes were worse than those of the earlier period. It is worth mentioning the copper stove with the "Shisou" style. Experts on the verification of this type of bronze have different opinions: British bronze expert Rose Kerr proposed in her book "Late Chinese Bronze" that "Shisou" was the "trademark" of a Jiangnan workshop that began in the late Ming Dynasty (Rose Kerr , Later Chinese Bronzes [Victoria & Albert Museum, London, 1990]); another expert Paul Moss disagrees. In his book "The Second Bronze Age", he believes that there were workshops in the late Ming Dynasty that specialized in casting "Shisou" style bronzes. No, "Shi Sou" is the legendary nickname of a monk who is good at making silver-inlaid bronze vessels. He believes that the bronzes with the "Shisou" designation are works from the 19th century. The picture below shows a "Shi Sou" style copper stove inlaid with silver wire. One said it was from the 17th century, and another said it was from the 19th century.

Edit this paragraph to determine the authenticity of Xuande furnaces

Because Xuande furnaces are valuable and there are many fakes on the market, how to distinguish these fakes is a headache for collectors A question. There are three main aspects to distinguish the authenticity of Xuande furnace:

Look at the patina

The authentic patina is warm and moist, containing treasure and will remain unchanged for a long time. Counterfeit products have dried up patina, and some look like paint, which becomes uglier the longer they are kept.

Look at the casters

The quality of genuine casters is average, and the quality casters are quite refined. Counterfeit castings are uneven, some are good and some are bad, or the casting is rough.

Look at the wear

Authentic products have natural and even wear, especially on the soles of the feet. The fake product has no wear or polish. Stove is an ancient device for burning incense and burning charcoal. It can be divided into incense burner, incense burner and hand and foot burner. The ancients advocated burning incense, and the incense burner has many uses. The main functions are three: first, it is used for lavender; second, it is a necessary tool for the study, as evidenced by the poem "Red sleeves add fragrance to the night reading"; third, it is used to worship gods. Buddha. The copper stoves cast during the Xuande period of the Ming Dynasty were for burning incense and offering sacrifices. They were specially made for large temples in the suburbs and were placed on the sacrificial table. The Xuande stoves had exquisite material selection, exquisite workmanship, and simple and elegant styles. precious. The Xuande period of the Ming Dynasty was the peak period for the production of copper incense burners. Xuande burners were rich in color. It was based on purple-red and had dozens of colors such as brown, cyan, green, red, blue, yellow, white, gold, etc. The structure of the furnace consists of three parts: furnace ears, furnace body, and furnace feet. Stove ears include: elephant ears, lion ears, ring ears, etc., which are placed in pairs on both sides of the furnace body. Some furnaces have no ears and no decorations on the furnace body; sometimes small pieces of gold foil are knocked on the outside of the furnace body.

The Xuande stove has thick walls and feels heavy when held in the hand; the markings are standard and dignified, and most of them are placed on the bottom of the outside of the stove. According to records, the Xuande furnace was only cast once in the third year of Xuande, with a quantity of 5,000 pieces. After that, the furnace was closed and no longer cast. Because the Xuande copper furnace is famous all over the world, there are many imitations in later generations. However, no matter how they are imitated, its color and copper quality are far from the real Xuande furnace. The wear of the casters is worth a lot of money

The quality of the casters remains stable for a long time and the quality of the high-quality casters is quite precise and the wear is natural and even

Edit the color quality of the Xuande furnace

After 6 to 12 refinings in the Xuande copper furnace, it is basically close to pure copper, so the color is purple-red. Although gold and silver and other materials are added, the quantity is small and the color quality of the finished product is not changed much. Therefore, the imitations after Xuande did not dissolve gold into the copper material in the casting furnace, but decorated the surface of the furnace with gold sprinkling, gilding, gold interlacing, gold cutting and other techniques to achieve a beautiful effect. The surface of the Xuande furnace has been oxidized for a long time, forming a maroon red oxide layer. This is the basic color to distinguish between authentic and fake Xuande furnaces. During the smelting process of Xuande furnace raw materials, the different alloy compositions will also cause some differences in the color of Xuande furnace materials, and also lead to differences in the color of the oxide layers on the surfaces of these copper alloys. But it remains unchanged, and the surface color of the real Xuande furnace is consistent with the maroon red color. Therefore, it is very clear to distinguish the true and false Xuande furnace from the surface color. If the oxide layer on the surface of the copper furnace appears black or black with a green tint, it means that the lead content in the copper material is too high and it is not pure copper; if green rust forms on the surface of the copper furnace, it means that the tin content is too high and is close to a bronze alloy; if If the surface of the copper furnace turns yellow and rotten when rubbed, and the oxide layer is not dense, it means that the zinc content is too high and it is a brass alloy. Judging from the surface texture, if it is oxidized and rough, uneven, or can see blisters, it is brass alloy casting or blister copper casting. In terms of weight, a furnace with a diameter of 12 cm weighs about 1 kg or more, a furnace with a diameter of 15 cm weighs about 1.7 kg or more, a furnace with a diameter of 18 cm weighs about 3 kg or more, considering that the thickness of the furnace wall is the same case, approximate the volume of a semicircular spherical ring.

Edit the features of this paragraph

First, there are many raw materials. In addition to copper, there are also precious materials such as gold and silver added, so the furnace quality is particularly delicate and dark purple or dark brown. Second, the refining process is complicated. Generally, the furnace materials need to be refined four times, while the Xuande furnace needs to be refined twelve times, so the quality of the furnace will be more pure and fine, like baby skin. The third is the golden light. The gold-plated or gold-embedded Xuande furnace has a golden light, giving people a feeling of being an extraordinary vessel. There are very few Xuande furnaces handed down from generation to generation, and their prices are astronomical and very expensive. Therefore, all dynasties have imitated them one after another. Nowadays, many imitations are flooding the market. No matter which flea market or antique store you go to, you can see the Xuande furnace "Made in the Xuande Year of the Ming Dynasty". However, if you want to find the real Xuande furnace from here, it is simply It's like finding a needle in a haystack, but things are not absolute. There are always fish in the river. Maybe we will encounter the genuine article at an antique stall. So how do you determine its authenticity? This requires you to master some identification knowledge. In fact, the easiest thing to identify among antiques is the Xuande incense burner, because there is a huge difference between authenticity and fakeness. It is usually considered difficult to identify the Xuande incense burner because you have never seen a real Xuande incense burner. Once you see a real Xuande incense burner, it is clear at a glance whether it is genuine or fake. When identifying, you must first know that the authentic Xuande furnace uses a kind of wind-milled copper. After repeated refining, gold, silver and other precious metals are added to the copper. In this way, the more it is burned, the purer it becomes. Gold and silver and other precious metals will float on the surface, and when gently wiped, they will become shiny. Therefore, the copper is said to be very fine, and the counterfeiters do not know it. Added gold and silver and other precious metals. The most wonderful thing about Xuande furnace is its color. The color of the fake Xuande furnace is dazzling on the outside, but the color of the real Xuande furnace is integrated into the inner substance, emitting a wonderful luster from the dimness, just like a beautiful woman, her skin is smooth and delicate, inviting to caress. The Xuande furnace has been burned on the fire for a long time, and the colors are bright and changeable. If it is placed on the fire for a long time, even if it is thrown into the mud and the mud is wiped off, it will still be the same as before. After ten years, once the fire is gone, it will be described as withered.

Inner cavity characteristics

The shape of the Xuande furnace is only its appearance, referring to the inner cavity of the furnace. The inner cavity of the Xuande furnace also has appreciation and dating value, reflecting the ingenuity and aesthetic taste of the times. I feel that Mingjiang pays more attention to the shape design of the inner cavity, especially to express the depth of the furnace cavity (horizontally and vertically). The horizontal sense of depth is expressed by the large arc, and the vertical sense of depth is expressed by the depth of the furnace cavity. There are several features that fully reflect the ingenuity: A. The furnace wall is unequal in thickness, thick at the top and bottom, and thin in the middle.

B. The furnace mouth wall is straight and angular as it transitions toward the inner cavity. C. The bottom of the inner cavity is low. D. The bottom diameter of the inner cavity is small. E. The most convex part of the inner cavity is lower than the most convex part of the outer shape. The significance of these features: The low bottom of the inner cavity is to increase the vertical sense of depth. However, if the bottom is low, the vertical midpoint of the cavity (the most convex part of the inner cavity) must be low, otherwise it will not look good. Therefore, the most convex part of the inner cavity must be lower than the most convex part of the shape. But if we want to create this effect , it must be that the furnace walls are not of equal thickness. If the bottom of the inner cavity is low, the diameter of the bottom must be small (due to the thickness of the furnace wall). The visual effect is to increase the horizontal sense of depth. Because the bottom diameter is small, the curvature of the lower half of the cavity becomes larger, so the inner cavity The low bottom of the cavity also increases the sense of lateral depth.

Gold-containing and polishing furnace

Many collectors believe that the Xuande furnace contains gold. Some people believe that the "snowflake gold" spots on the surface of some copper furnaces are a reflection of the gold contained in the copper. Some people think that if the specific gravity of Xuande furnace exceeds that of copper, it must contain gold. "Snowflake gold" is a color stain, not gold in copper, because even if gold is added to copper, the finished product cannot be in a state where gold and copper are separated. The specific gravity of some Xuande furnaces is greater than that of copper, but this does not mean that the furnaces contain gold. There are many metals with specific gravity greater than copper. It is possible that other metals with heavy specific gravity were added to the casting of these furnaces. Rose Kerr, the head of the East Asia Department of the Victoria Museum in the United Kingdom, once conducted a composition analysis on the Xuande furnaces in the collection of the Victoria Museum. She concluded that the majority of the furnaces were brass containing 29% to 35% zinc, and no gold was found in them. ingredients. Foreign reflow polishing furnace. With the development of the economy and the expansion of the collection team, the return of cultural relics is developing in depth, and Xuanlu is no exception. Most of the Xuan furnaces returned from abroad have been cleaned. Because of their bright appearance, these stoves may be considered fake stoves by beginners, but in fact, it is easy to distinguish the stoves that have been cleaned and the fake stoves that are made now. Look at the following aspects: First, look at the inner cavity. The rust, incense ash or soil in the inner cavity of the furnace after cleaning the leather shell is basically retained. There are many abrasions or irregular green rust accumulation on the inner cavity wall near the lip, which is completely different from the newly made fake furnace. Secondly, look at the turning points such as ears and feet. There are many gaps in the furnace that have been cleaned. There are white or bluish-white green powdery residues in these gaps. The third is to look at the model. Models that have been cleaned by the leather shell furnace have residual rust or greenish-white powdery residue in the strokes. Fourth, look at the feet of the furnace. The furnace that has been cleaned has obvious wear and tear on the soles of the feet, and the copper color of the stressed contact surface is slightly lighter than other copper colors. In these furnaces whose skins have been cleaned, the defects of the furnace (such as repairs, impact marks, etc.) and the roughness of the copper can be seen at a glance. Since the leather shell is polished rather than new copper, the color of these stoves will gradually darken after being stored for a period of time, taking on a warm old copper color. Some collectors think that these furnaces have been passed through the leather shell and are not worth collecting, but I think it is worth broadening their thinking. In terms of skin shell alone, although these furnaces are not as good as those with undamaged original coating, they are at least no worse than furnaces that have been exposed to soil and are heavily rusted and mottled. A cleaned furnace can show off the beauty of the furnace's copper quality. If you play with furnaces that focus on precision and copper quality, these furnaces with clear leather shells are also worthy of your favor. Since 2004, this type of stove with bright appearance has often appeared in Christie's auctions, with good transaction rates and transaction prices.

Edit this section on the difference between fine and rough furnaces

The ancients strived for perfection in Xuande furnaces. Today’s people play with furnaces regardless of the age, but they must distinguish between fine and rough furnaces. The author believes that accuracy and quality are the lifeblood of Xuande incense burners. Whether in terms of identifying fakes or collecting them, accuracy should be the main focus. The accuracy of the Xuan furnace is mainly reflected in the following aspects: A look at the shape: The shape of the fine furnace is regular, with good symmetry from any angle, the edge is very flat, and the ears are regular. A rough furnace will be crooked and uncomfortable. Second, look at the copper quality: The copper quality of the fine furnace is very pure and has good luster, and the surface of the furnace feels as smooth as baby skin. The copper of the furnace is not refined, looks dull and has a dull luster. Third, look at the style of the incense burner: the style of the refined incense burner is full of charm and craftsmanship, the calligraphy is neat, the words are clean and neat, and the ground seals are smooth. The calligraphy of the inscription on the furnace is poor, with serious trachoma in the strokes and ground seals. Fourth, look at polishing: The polishing of the fine furnace is very detailed. The best ones can polish away the tiny trachoma caused by lost wax casting, so that the surface is extremely smooth. The polishing of rough furnaces is rough, and some have not even been finely ground, and there are still bruises on the furnace body. For the same type of stove, the difference between a high-quality fine stove and a crude stove is no less than the difference between high-grade official kiln porcelain and crude folk kiln porcelain.

If shape and style (such as private money and calligraphy types) can enable us to distinguish types of furnaces horizontally, then precision can enable us to extend the distance between furnaces vertically. Combining the two, playing with the furnace will be a variety of fun. The above are the general characteristics of looking at fineness and coarseness. Accuracy and quality have different emphasis at different times. Ming stove emphasizes charm, whether it is the overall or detailed design, it is thought-provoking. The furnaces of the late Ming and early Qing dynasties have a simple and heavy feel. The furnaces in the Yongzheng period had soft lines, while the fine furnace craftsmanship in the Qianlong period reached a historical high.

Judgment Criteria

Usually, there are three main aspects to judge the quality of Xuan furnace: 1. The most important thing is to look at the patina and color. It is said in old times that there are five colors, namely Buddhist scripture paper, chestnut shell, eggplant peel, Tang pear, and brown, among which the color of Buddhist scripture paper is the first. Among the 1995 auctions of Duoyunxuan in Shanghai is a copper stove (19.2 cm high), whose color can match the color of Buddhist scripture paper. In addition, the value of some gold-sprinkled or gold-inlaid copper furnaces manufactured using special techniques is several times higher than ordinary copper furnaces. 2. Secondly, look at the shape, caster, size and weight. The shape should be quaint and rich. Those with ears and feet are better than those without ears and feet. The more refined the casters, the better. In terms of size, furnaces with a diameter of 8-12 centimeters are the most common and are small; furnaces with a diameter of about 15 centimeters are medium-sized, with fewer quantities than small ones, but are more valuable than small ones; and furnaces with a diameter greater than 20 centimeters are medium-sized. Large size, rare in craftsmanship, and very valuable. In the case of the same size, the heavier the furnace, the higher the value. For example, the Xuan furnace from the late Ming and early Qing dynasties collected by friends has a diameter of only 15.8 centimeters and a weight of up to 7 kilograms. It is a super heavyweight among copper furnaces of this size, and its value is several times higher than the ordinary one weighing 3 kilograms. 3. Finally, look at the quality of the item. The more refined and unique the model, the better it can help date it, and the higher the value of the copper furnace. Xuande furnaces were cast in the Ming, Qing and Republic of China, but how to determine the age? In terms of overall shape, the overall style of the Ming Dynasty copper furnace is elegant and vigorous. By the late Ming and early Qing dynasties, copper furnaces were still robust, but not as elegant as the earlier ones. By the 18th century, the style began to become more delicate, and efforts were made to change the shape and decoration. Some were elegant, but overall they lacked richness. The two pictures below are from the author's collection. They were originally sold at Christie's in London. They are 31.8 cm high. They are from the Qianlong period and the Qianlong period. The decoration is more complex and the coral inlay is intact.

Color quality of the furnace

After 6 to 12 refinings, the Xuande copper furnace is basically close to pure copper, so the color is purple-red. Although gold and silver and other materials are added, The quantity is small and the color quality of the finished product is not changed much. Therefore, the imitations after Xuande did not dissolve gold into the copper material in the casting furnace, but decorated the surface of the furnace with gold sprinkling, gilding, gold interlacing, gold cutting and other techniques to achieve a beautiful effect. The surface of the Xuande furnace has been oxidized for a long time, forming a maroon red oxide layer. This is the basic color to distinguish between authentic and fake Xuande furnaces. During the smelting process of Xuande furnace raw materials, the different alloy compositions will also cause some differences in the color of Xuande furnace materials, and also lead to differences in the color of the oxide layers on the surfaces of these copper alloys. But it remains unchanged, and the surface color of the real Xuande furnace is consistent with the maroon red color. Therefore, it is very clear to distinguish the true and false Xuande furnace from the surface color. If the oxide layer on the surface of the copper furnace appears black or black with a green tint, it means that the lead content in the copper material is too high and it is not pure copper; if green rust forms on the surface of the copper furnace, it means that the tin content is too high and is close to a bronze alloy; if If the surface of the copper furnace turns yellow and rotten when rubbed, and the oxide layer is not dense, it means that the zinc content is too high and it is a brass alloy. Judging from the surface texture, if it is oxidized and rough, uneven, or can see blisters, it is brass alloy casting or blister copper casting. In terms of weight, a furnace with a diameter of 12 cm weighs about 1 kg or more, a furnace with a diameter of 15 cm weighs about 1.7 kg or more, a furnace with a diameter of 18 cm weighs about 3 kg or more, considering that the thickness of the furnace wall is the same case, approximate the volume of a semicircular spherical ring.