Have you ever noticed that sometimes your homemade cold process soap develops a white residue on the top? Soda ash is caused by lye reacting with naturally occurring carbon dioxide in the air and forming sodium carbonate. The result is a scum-like crust over exposed soap. Luckily soda ash doesn't affect the soap's safety or usability—just the aesthetics. #diy#soap#soapmaking#homemade#handmade#soaplife#handmadesoap#soaps | what is soda ash | via @rusticwise