How to pronounce zaffer in English

"A pigment obtained usually by roasting cobalt glance with sand or quartz as a dark earthy powder. It consists of crude cobalt oxide or of an impure cobalt arseniate. It is used in porcelain painting and in enameling pottery to produce a blue color and is often confounded with smalt from which however it is distinct as it contains no potash. The name is often loosely applied to mixtures of zaffer proper with silica or oxides of iron