Halloysite is a natural form of very white kaolinite.

Like kaolinite, halloysite is an aluminosilicate, however, it has a tubular crystal structure, which is markedly different from the booklet or platelet crystal structure of kaolinite.

Halloysite and kaolinite are ubiquitous in soil and weathered rock, where they occur in a variety of particle shapes. They typically form through the hydrothermal alteration of aluminosilicate minerals and can occur intermixed with other minerals in kaolin rocks. Large halloysite-specific deposits are relatively rare, however.

Due to its high whiteness, high aspect ratio and nanosize halloysite is particularly sought after by ceramic tableware producers for its translucent effect in fine porcelain and bone china. The tubular shape also helps prevent sag before firing.

Physical properties:

- High whiteness

- High translucency

- Tubular structure

- Nanosize

- High aspect ratio

- Low iron and titanium content