Clay is a kind of layered silicate, and its lamellae are composed of silica tetrahedron and alumina octahedron.

According to its structure, it can be divided into the following four categories: kaolinite group, 1 type: 1 type. Montmorillonite/montmorillonite family, 2: 1 Illite (or clay mica) formation, 2: 1 type. Chlorite formation, 2: 1: 1 type.

It can be divided into ceramic clay, refractory clay, brick clay and cement clay according to their properties and uses. Hard clay is often in block or plate shape, generally insoluble in water, and has high fire resistance. It is the main raw material of refractory products. Hard clay in refractory clay is used to make refractory materials for blast furnaces, lining bricks and plug bricks for iron smelting furnaces, hot stoves and steel drums. In the ceramic industry, hard clay and semi-hard clay can be used as raw materials for making daily-use ceramics, building ceramics and industrial ceramics.

paper

Also known as "pulp clay" in China. The ingredients include pulp, gum, feldspar and fiber. There is no need to barbecue, and the texture after drying is between clay and gypsum, which will not be broken and can be preserved permanently without deformation. It can not only be carved, but also attached to various objects for pasting and shaping, and can be well matched with stone, wood, glass and so on, so it is widely used. Ordinary paper clay is white and can be colored after drying. Waterborne and oily pigments can be used, and watercolor, acrylic and oil painting pigments can be used, which is non-toxic and tasteless.

With the development of technology, paper clay is more delicate, lighter and more viscous, which can be used to make exquisite handicrafts, and colored paper clay appears. This kind of clay has been popularized in some foreign countries since 1970s, and is usually used in children's sculpture classes. It has become a popular hand-molded material, and many of the works created have become fashionable decorations and have been integrated into daily life. There are two kinds of resin paste, one is bread flower (flour paste). A saying that bread flowers originated in Latin America, local people collect leftover bread crumbs, dry them and grind them into powder, and add white mucus to make "flour clay". But this kind of flour clay is not malleable enough and strong enough. Air-dried works are easily broken and cannot be placed for a long time. Later, this simple process spread to Japan, and the Japanese improved it by adding preservatives and other chemicals to make flour clay. This kind of flour clay itself is translucent and soft, and can be stretched to be very thin without cracking. Even after drying, it can maintain elasticity and make fine products freely. Strong plasticity, strong texture and simple use. You can use oil painting pigments and acrylic pigments to color, then shape the image in your mind and dry it naturally. The finished works can keep the same shape and can be used to make flowers, small animals, dolls, ornaments and other works. Clay is most suitable for flowers, which can be stretched to a very thin thickness to make a light and natural feeling. However, the produced works are relatively dull, and after drying, oil painting pigments must be coated on the surface of the works to increase their aesthetic feeling and three-dimensional sense.

There is also a kind of resin clay, which is very dry and hard to take out, but it feels broken. But after adding color, it becomes softer and softer, and the works made are very hard, suitable for making some mini-utensils, such as bowls, plates and flowerpots. rock flour/powder

Fine texture, good ductility, dry strength and stone texture. Easy to mold and carve. It is most suitable for human form and wall decoration.

Woody class

Made of natural wood, it becomes hard after drying and can be carved into a sharp shape, which is suitable for products with wooden style.

mercery

Liquid clay, delicate and soft. Very suitable for all kinds of fabrics. The surface of the finished product is treated with cloth mud, and the effect is completely different.

silver

Also known as sterling silver clay, it can be widely used in DIY manual combination of jewelry, clay and metal, and can be easily burned into fashionable and beautiful sterling silver jewelry and gifts of various shapes.

List of clay types Clay types Kaolin spherical clay refractory clay was mostly generated in Cenozoic, and Cenozoic was mostly the order degree of Paleozoic kaolinite.

(Cover thickness) is mostly disordered.

(thin or none) is mostly disordered.

(very thin) basically orderly

(very thick) kaolinite crystal form

(current treatment) often self-forming, semi-self-forming.

(not carrying) often irregular.

(Long-term handling) is often irregular

(Long handling) The grain size/micron is mostly 5 2 2 5 2 5 6 5438 0580 65438 0580 5% refractoriness/℃.

(Example/℃) Narrow

(1500 ~ 1570) width

(1320 ~ 1550) is slightly wider.

(1300 ~ 1390) iron and titanium content

Usually less (whiteness)

(greater than 70 ~ 80) is often more.

(less than 50 ~ 80) is often more.

(less than 50 ~ 70) organic matter

(plasticity) not often containing a small amount.

(can be improved) often contains a small amount.

(unable to improve) major genetic residual deposits.