China Clay

From Cargo Handbook - the world's largest cargo transport guidelines website
Infobox on China Clay
Example of China Clay
China Clay.jpg
Origin USA, Europe, Russia, China
Stowage factor (in m3/t)
  • 1,46/1,70 m3/t (bags)
  • 1,13 m3/t (bulk)
Humidity / moisture -
Ventilation -
Risk factors -

China Clay


A white or greyish powder, crystals or pellets; activated by sulphuric acid. May absorb water up to many times its own volume.

This commodity is well known as Kaolin. Other names are: Porcelain clay, Cornish clay, Argilla, White Bole, Pipe clay, Porcelain earth and Catalpa. The purest form of clay (a silicate of aluminium) used in the manufacture of china, distemper work and other purposes.

Kaolinite is a mineral belonging to the group of Aluminosilicates, and insoluble in water and organic solvents. It is commonly referred to as "China Clay" because it was first discovered at Kao-Lin, in China. The term Kaolin is used to describe a group of relatively common clay minerals dominated by kaolinite and derived primarily from the alteration of alkali feldspar and micas.

Kaolin is a soft, plastic clay mainly composed of fine-grained plate-like particles, usually light to dark grey, comprising of 10% soft lumps and 90% soft grains. Kaolin is formed when the anhydrous aluminium silicates which are found in feldsparrich rocks, like granite, are altered by weathering or hydrothermal processes. The process which converted the hard granite into the soft matrix found in Kaolin pits is known as "kaolinisation". The product has a high fusion point and is the most refractory of all clays.

Used as a filler and coating for paper, and in the manufacture of refractories, ceramics, cements, fertilizers, chemicals (especially aluminium sulphate), catalyst carrier, anticaking preparations, cosmetics, insecticides, paint, source of alumina, adsorbent for clarification of liquids, electrical insulators.

See also Aluminium Silicate

Shipment / Storage

A white or greysih powder shipped in bulk and sometimes in paper sacks.

When possible accepted for carriage in DC/Bulk always an inner liner to be added first to avoid difficult and costly extra container cleaning.

China clay slurry is usually shipped in specialist carriers on account of its liability to shift.

The carrying vessel needs to be cleaned, as particles of rust, coal, etc., entail considerable work and expense in cleaning the clay.

To be handled carefully and kept absolutely dry.

When china clay is intended for use in the manufacture of paper or ceramic ware, such as bone china pottery, damage by salt water and other contaminants renders the clay useless.

Risk factors

See IMDG Books. Listed under Clay in the Code of Safe Practice for Solid Bulk Cargoes in the supplement to the IMDG Books under Clay.