Galalith
（重定向自Erinoid）
![White galalith RAAF pre-1953 buttons. (Top left button shows crazing resulting from button having been heated during washing.)](/Images/godic/202501/11/White_casein_Australian_Royal_Airforce_pre-1953_buttons2717.jpg")
![Chemical reaction of two proteins (top) with formaldehyde (H2CO) – schematic presentation.](/Images/godic/202501/11/Galalith_Synthesis_SCHEMATIC_V12718.png")
Galalith (Erinoid in the United Kingdom) is a synthetic plastic material manufactured by the interaction of casein and formaldehyde. Given a commercial name derived from the Greek words gala (milk) and lithos (stone), it is odourless, insoluble in water, biodegradable, antiallergenic, antistatic and virtually nonflammable.