What is china Clay and what is it used for? Does China/White Cosmetic Clay have any benefits on our skin? For answers to such questions read to understand the benefits side effects and properties of china/kaolin clay
What is China Clay?
China clay is a fine soft white clay and, as the name suggests, it was first used in China in making ceramics. They occur naturally in soils and develop from the process of chemical weathering in moist and hot climate such as tropical rain forest. It is also known as white clay, White Cosmetic clay, Kaolin, Hydrated Aluminum Silicate.
These materials are named after Kao-Ling Hill in China from which it was initially mined for centuries. The samples of China clay were initially sent to Europe around 1700 by French missionaries as examples of materials for use in China to make porcelain.
China clay is used in making porcelain, rubber, textile, tiles, paint, paper and in making several other products.
Common China Clay Uses
- It is commonly used in ceramics because of its white burning and high fusion temperature, which makes them suitable in the manufacture of white white-ware, refractories and porcelain.
- It is usually mixed with silica and feldspar in equal amount and ball clay in smaller amount to make White-ware. These components provide it with shrinkage and plasticity properties needed in the formation and firing the ware. However, they are used in isolation to make refractories. About 40% of China clay produced is used in coating and filling of paper.
- In filling, China clay is mixed with cellulose fiber to give it the color, printability, body and opacity to the paper sheet.
- In coating, they are also plated with adhesive on the surface of the paper to give color, opacity, gloss and printability.
- Very pure and fine grains of kaolin are used to fill rubber to help improve their resistance to abrasion and mechanical strength.
- In painting, it is used to as a flattening and extender agent.
- It is also an important component in making cosmetics, organic plastics, ink and other products that require the fine grains, chemical inertness, whiteness and absorption properties.
Benefits of China Clay on Skin
- China clay has unique physical and chemical properties for healthy skin benefits as well as side effects. External use of this substance has a long history and benefits to the skin. Traditionally, it has been used to care, nourish and soothe different types of skin.
- It is currently one of the main components in most skin and facial products, deodorants, body powders, poultices and scrubs.
- China clay is effectively used in caring for oily and wet skin. It is applied as a dusting powder on the skin or in a wet dressing and left to dry before it is washed out. It works by minimizing the production of sebum to make the oily skin remain dry and smooth.
- The high content of silica in the clay removes dead skin, making it to regenerate. This together with Phyto-nutrients and unique minerals helps in detoxifying, purifying removing oil from the skin and make it moist.
- China clay is effectively used to treat and heal different types of skin conditions. An example is gastrointestinal tract to heal soreness and swellings in the mouth resulting from radiation treatments.
- It is also combined with other products to treat inflammation and cancer of the large intestine.
- It offers a protective coating to the tract lining or epithelia to prevent damage caused by irritant hydrochloric acid and drug radiation that cause inflammation and cancer.
- As a topical emolument, the clay is used treat conditions of the skin such as muscle soreness, pain and aches as well as inflammations, cuts, insect bites, bruises, boils cold sores and zosters.
- It has the ability to increase circulation of blood to the skin, thus facilitating the healing process of the skin.
Side Effects of China Clay
China clay has a few severe toxicity and few side effects because it is not systematically absorbed.
- Prolonged exposure to Kaolin clay may also cause pneumoconiosis and other lung problems.
- Regular consumption of the clay may also lead to low birth weight, constipation, rupture colons, low level of blood hemoglobin and malnutrition.
Physical properties of China Clay
- Pure natural China clay is white in color.
- However, the color of impure clay may vary when mixed with other substances. For example, it may appear pink-orange when it is mixed with iron oxide and light orange to yellowish when combined with Feldspar or aluminum silicate.
- The clay may look brown when it is mixed with sand.
- Kaolin clay occurs in the form of crystals of different sizes.
- The clay is hexagonal in shape with platy layers when viewed under an electron microscope.
- It has earthly texture, soft powder with low capacity to swell and shrink. This implies that wet white clay has a low ability to expand and low contracting ability when it is dry.
Chemical Properties of China Clay
Kaolin clay is inert because it does not react with other elements at different temperatures and PH level. This explains why the clay exists naturally as a free agent. The chemical name Kaolin clay is a hydrous aluminum phyllosilicate (Newton, 2009).
China clay does not dissolve in water, rather forms a slurry suspension in water. The cation is very low with exchange aptitude in the range of 1-15 mEq/100g. This indicates that White clay can hold a very small amount of cations at any given level of PH. In other words, China clay is less reactive, but it can change under extreme temperature of over 500 degrees Celsius.
Common Questions on China/White Cosmetic Clay
Kaolin Clay vs Bentonite Clay – Is Kaolin Clay same as Bentonite Clay?