Chinese pigment

Chinese pigments (中國國畫傳統顏料) are the traditional medium to execute traditional Chinese brush paintings, besides ink. Chinese pigments is similar to Western gouache paint in that it contains more glue than watercolours, but more so than gouache. The high glue content makes the pigment bind better to Chinese paper and silk as well as enabling works of art to survive the wet-mounting process of Chinese hanging scroll mountings without smudging or bleeding.

Traditionally, Chinese pigments come in form of chips, cakes or powder made from natural plant and minerals. Some of these require preparation by adding glue (明膠) before they can be used. Traditional pigments require some skill and knowledge to mix as some pigments do not blend well with others (e.g. herbal and stone colours generally do not combine well). Also, layering a different pigment on top of another can create different effects depending on the type and transparency of the upper layer pigment.

Synthetic versions that already contain glue come in tubes and are more convenient.

Out of the many pigments used for traditional colours, around 12 are basic colours that are widely used. Some of the pigments use natural plant ('herbal') or minerals ('stone') that are poisonous or toxic. Outside of these traditional pigments, other colours are made from synthetic chemicals.

All traditional yellow pigments are toxic. Because of this, modern synthetic substitutes are often used.

In modern practice, painters tend to use white gouache paint as a substitute to traditional whites, typically for underpainting.

...
Wikipedia