Ladies-- I bought the anthracite colored Jimmy Choo Hunter boots last year, and I just took them out-- as predicted they are covered in that white stuff! Turns out the special Hunter spray says 'not for metallic surfaces.' I already have the Hunter sponge but it's not sufficient for the huge amount of white gunk. Have any of you tried the spray on metallic hunters? I am a bit scared to but I don't see any alternatives? Any ideas?