affination
/ˌafɪˈneɪʃn/noun
1 Metallurgy. The process of refining (precious) metal, especially by treatment with hot concentrated sulphuric acid.
2The initial process in the refining of sugar whereby raw sugar crystals are treated with a warm syrup to remove the thin layer of molasses.
Origin
Mid 19th century; earliest use found in Catalogue of the Great Exhibition. From affine + -ation.