The top grade in Tian Huangshi, the whole stone is clear and transparent, like solidified honey, moist and incomparable.

Silver-coated gold: a fresh egg, wrapped in golden yellow like an eggshell, has a pale white skin outside, which is very precious and bright.

Baitianshi: The white stone in Tiankeng Stone is called "Baitianshi", which is mostly produced in Shangzhong and Nakasaka. The color of Baitian stone is not pure white, mostly yellowish or egg blue, which looks like rich jade, with obvious radish lines, red tendons and blood sample checks. The fine texture and less checks are better.

Gold-coated silver: Tian Huangshi is the top grade, like sheep fat oil, with a bright yellow skin outside, which forms a sharp color contrast with meat.

Chicken oil yellow: produced at the junction of the upper half and the middle half, thin and solid, moist and greasy, and the stone surface color has a layer of chicken oil-like skin.

Orange peel yellow: stone carvings are produced in the middle plate area, with bright color, red and yellow, and pure texture.

Black leather field: also known as "crow skin", the color is mostly osmanthus, and the skin is like lacquer charcoal. The contrast between the black skin on the outside and the yellow skin on the inside is particularly strong when carving works with this kind of stone. Xiguantian: Xiguantian refers to stones that are accidentally scattered in Shoushan Creek, or exposed due to farming, and thrown into the Creek. They are mainly piled up near Zhongguanwu in Zhongbanxi, hence the name "Frozen in the Creek". This kind of tiankeng stone has been accumulated in the stream for a long time. The stone is quite bright and clean, slightly pale in color, with extremely thin cortex or no radish pattern.

Hard field stone: Any field stone with poor texture, insufficient moisture, no psychic ability and many impurities is collectively called hard field stone, which is the inferior product of Tian Huangshi.

Red field with orange peel: mainly produced in Shangban and Zhongban. Also known as "Red Square" and "Red Square Stone", the Red Square with orange peel is called "Red Square with orange peel" as its name implies. Hongtian is extremely rare, and it is extremely rare to have a red date. Its texture is tender, moist and slightly transparent, and its texture implies radish grain, which is a rare stone species. The above image sources: 1, Hong Tianshi _ Baidu Encyclopedia; 2. Tian Huang frozen stone, Jin Bao Yin and crow skin Tian Huang are from "Chushan Studio Variety Field Huangshi (Collection)".

In today's international art market, Tian Huangshi's buyers are mostly Hong Kong, Taiwan Province Province, Singapore and other Chinese-inhabited areas. The better the quality of Tian Huangshi, the more attractive it is to collectors.

Tian Huangshi is only produced in Shoushan, Fujian, China. Because its color is generally yellow and it is produced in the field, it is called Tianhuang. The material of Tian Huangshi is warm and greasy, and it is known as the "crown of lithographs". The aesthetic expression of China seal is in three aspects: seal cutting, button decoration and print quality. The precious Tian Huangshi became attached to the seal, which not only enriched the aesthetic value of the seal, but also doubled the value of Tian Huang himself. The color of Tian Huangshi is based on calm and pure deep yellow, which symbolizes wealth. A first-class Tianhuang Yin Shi should not only have delicate and moist characteristics, but also have pure color, bright texture, huge body and finely carved buttons. If the printing surface comes from a famous seal cutting, its value will be higher. Yellowstone in the collection can be divided into old stone and new stone. Generally speaking, old stones are more positive in quality and shape, while new stones tend to follow the shape naturally in order not to reduce the weight, and are rarely processed into square printed matter. Tian Huangshi has a unique grain, which is often called "radish silk grain". Some people often use this as the basis for identifying Tian Huangshi. But in fact, some stones with "radish silk pattern" are not Tian Huang, and can't be judged by just one grain.

Tianhuangshi is a rare shoushan stone. Theoretically, pyrophyllite (Al2[Si4O 10](OH)2) is monocotyledonous. The theoretical value of its chemical composition: SiO 2 66.7%; H2O 5%； al2o 3 28.3%； fe2o 3 1.7%； Cao is about 0.3%; It may also contain trace amounts of potassium, manganese, titanium and zirconium ............................................................................................................................................................... The friction of sulfur is about 2 degrees and its specific gravity is 2.5. The fire resistance limit is about 1700℃.

Shi Tian-produced in streams and fields in Shoushan Township. There is a pothole on the ground, and there is a stream next to it, which is about several miles long and is Shoushan Stream. Usually, the range of paddy fields irrigated by streams is taken as the boundary of producing fields and stones. Its varieties are divided into upper half, middle half, lower half, lower half and six fields, among which the field stone produced in the middle half is particularly excellent. Color bonus, yellow, white, black, etc. Red people are called "Red Square", yellow people are called "Tian Huang", white people are called "White Square" and black and gray people are called "Black Square". There are also "Jintianyin" with white outside and yellow inside, "Jintianyin" with yellow outside and white inside, and "crow skin field" with thin black outside.

(1) Orange Peel Red Square: Orange Peel Red Square is produced by the last three shifts. Pigments are mainly red and yellow, especially deep red. The color is like orange peel, but deeper and thicker, like red amber, but more gentle and amiable than amber. The texture is extremely delicate, and it wants to melt. Its quality is pure and excellent, and it is the most saturated color in the field. Orange peel red should be a red field, accounting for the least proportion of field stone production, and the volume is not excessive, so it is extremely rare. The orange peel red with good material and shape is listed as the best in Shi Tian.

(2) Braised red fields: Braised red fields are mostly produced in Shangbantian and Zhongbantian. The outer layer is as red as red dates, and there are often black patches on the surface, such as black skin. The volume is also very small, and the brightness is lower than that of Orange Peel Red Square. Microscopically transparent, the quality is slightly harder and drier than Tianhuang, and there are often no obvious radish lines.

According to legend, Oda yellow in soil is a rare product because it is smoked and burned by fire when burning grass in stone farmland, and it changes color when it reaches a certain temperature. However, most of them are not cherished by collectors because of their dry texture and less materials.

③ Tian Huang: refers to the yellow Shi Tian. It can be found in the creek fields of Shangban, Zhongban, Xiaban and Xiaban, as well as in places that go down the river for several miles to Shuangxi, accounting for the largest field stone output. The yellow color of each cherry is slightly different: the upper cherry is tender and light; Under Sakamoto, it is hard; The color quality of Nakasaka is the best. Yellow has different shades, and people divide it into three grades and ten categories according to its hue:

1, the standard tianhuang color is top grade.

The color (1) is thick, slightly orange, close to orange peel red, but slightly less red, so it is called "orange peel yellow".

(2) Red and bright yellow is called "golden yellow".

(3) Yellow with ochre, such as mature or ripe loquat color, is called "loquat yellow".

2. China products

(4) Yellow is "osmanthus yellow", which is yellow but slightly pink.

(5) It is lighter than osmanthus, greasy and tender, and slightly yellower than Baitian, which is called "chicken oil yellow".

(6) Those that are yellow and slightly brown like ripe chestnuts are called "ripe chestnut".

3. Inferior products

(7) It is slightly lighter than the ripe chestnut, and it is "soap yellow" when it is sluggish.

(8) It is dark brown and deer-like, so it is called "sugar yellow".

(9) Yellow is as light as beeswax, and its quality is more yellow than chicken oil, which is called "dense wax yellow".

(10) between osmanthus yellow and soap yellow is called "sweet potato yellow".

These four kinds of fields are relatively dry and rough, almost psychic, and there are no radish patterns, commonly known as "miscellaneous fields".

(4) Baitian

Refers to Bai Tianshi. Dig from above and in the middle, it is greasy and smooth, like a pit crystal. There are often bloody ochre yellow squares, and the radish grain is as delicate as the fresh white radish grain. Because the stone is psychic and pure and light in color, the lattice and grain are more obvious and elegant than all kinds of field stones. Baitian occasionally has black skin, which is also colored, white and turbid, and looks like sand. Most patches go deep into the texture, like snowflakes. White fields with yellow skin, the so-called "gold covered with silver", are extremely difficult to find. Their colors are not pure white, but slightly yellowish or egg blue, and their textures are yellow and red under the light, which is different from digging white mountains.

(5) Kuroda

There are two kinds of black fields: pure black and gray black.

Pure black field refers to black ochre field. Most of them come from Tietouling and Tanaka in Xiaban area, and there are often yellowstone skins. The quality is also fine. Radish grains are slightly thicker than other colored fields, and the texture is turbid and slightly transparent, often accompanied by tiny black sand nails.

The gray-black fields are brighter and grayer. The skin is black or yellow, thick and hard, with black sand spots and muddy appearance. Radish lines are often rough. In addition to the above, Shanghai and Nakasaka also often produce. The next product area.

Occasionally, there is a black field with fine texture and fine texture, which is grayish black and blue-green, sometimes called "green field".

(6) Black leather field

That is, the "crow skin" field. There is a slightly transparent black stone skin outside. Produced in the upper, middle and lower branches. The skin is not pure black, and the black is slightly turquoise or grayish green, also known as "toad skin". In its skin, there are white fields or yellow fields with the same color and texture as ordinary fields without skin, except for small black nails. You can see a single layer of crow skin through the lamp, and its muscles are easy to identify. If there is one or two layers of yellow or white skin in the crow's skin, it is difficult to identify it under the light. However, this kind of field stone with multi-layer stone skin, if the skin is fine, without mottling and sand spots, is more common that the color and quality are good, just like frozen stone, which is a rare material.

(7) Gold covered with silver refers to the field stone with white outside and yellow inside.

Many white fields always have a yellow heart, and Tian Huang often has a white skin. "Silver-covered gold" originally refers to a field with more yellow hearts or a slightly thicker yellow skin, which is collectively called "silver-covered gold". The yellow heart of the former is also like the sweet potato with yellow heart. Huang Yiming is pure and elegant, and its quality is extremely delicate and greasy, while the grain is more subtle and difficult to find than all kinds of fields and stones, and it is almost invisible. The yellow color of the latter is mostly between golden yellow and osmanthus yellow, close to golden yellow, but slightly pink with fine radish lines. Silver-wrapped gold with good volume and good color also belongs to the top grade in Shi Tian.

(8) Xia Tian

Produce white pheasants and go to Sakamoto. The skin is bluish yellow and thin. The external muscle is thick in color, yellow-brown, and light in texture. Or there are obvious thin radish lines, slightly straight, accompanied by small white spots like lice eggs. The quality is penetrating, but there are many cracks.

(9) Set aside cultivated land

Also known as the skating rink. This is a field stone that moved downstream. There are occasional shallow sand layers on the surface of Shangsiban creek field or streams from Xiaban to Jiushou, Huilong and Shuangxi. Most of the lines are thick and exposed, with straight lines and some uneven density. The thick is extremely thick, and the thin is only a small part, just like ordinary tianhuang. How brown it is. It is often accompanied by a small piece of yellow skin, yellow and grayish green, rough and astringent as cheese powder. Texture is often accompanied by black sand nails or scattered white spots. Among them, the bare soil is exposed to the sun, and the front side often degenerates and becomes rough and cracked, while the back side does not lose its true color.

(10) Nine First Days

It is produced in the area from Xiaban to Shoushanxi at the foot of Shanbo Mountain. It is mostly excavated in deep sand, and the output is few and scarce. Its color is light and white, or brownish red. There are no lines or lines as fine as silk. More is thin yellow skin. Soft and tough, semi-psychic or micro-psychic, with few cracks and occasional scattered white spots or tiny black nails. Wetness is slightly worse than that of Shangsansaka's fields. The "Nine Tiger Hall" with strong color and high quality is usually classified as Xiabantian.

(1 1) hard ground

Refers to the fields and stones dug by Sakamoto, and the muscles are hard and thick. The skin looks like cow's egg skin or deer's eyelids, but the cortex is slightly thinner than cow's egg yolk, and the skin color is dark and slightly green. Rough texture or wireless strips or lines. Poor permeability, sometimes containing hard sand.