Casein paint

It generally has a glue-like consistency, but can be thinned with water to the degree that fits a particular artist's style and desired result.

One of the qualities for which artists value casein paint is that unlike gouache, it dries to an even consistency, making it ideal for murals.

Lime casein works well on porous surfaces, even outdoors, though it has a short shelf life and must be used with pigments that are balanced against the binder's low pH.

Borax casein has a shelf life of several weeks, is pH neutral, and can be used outdoors through the addition of linseed oil.

John Berkey continued to use casein in combination with acrylics in most of his paintings.