Galalith (casein plastic)
Galalith is a casein plastic made from milk protein treated with formaldehyde. It is a semi-synthetic plastic, not a natural stone despite its name referring to milk stone. Uses included buttons, buckles, jewellery and pen holders.
Colour and manufacture
Casein plastic could be dyed in many colours and supplied as sheets or rods for further working. The Powerhouse museum holds sample boards of galalith products made in 1933, showing raw material and finished articles. The German Plastics Museum highlights its hard, glossy surface and tendency to splinter.
Not another name for Bakelite
Bakelite is a different type of plastic. A glossy brooch or colourful button cannot therefore be identified securely as galalith by appearance alone. Record shape, joints, markings and damage, examining each component of a mixed-material object. Avoid burning, hot-needle or scratch tests at home. Establish the material before cleaning or polishing, and do not use its name as independent proof of age or maker.
Sources
Deutsches Kunststoff-Museum: Galalith; Powerhouse Collection: Samples of Casein plastic.
