Twenty four silver-plated aluminum coupons, three per soil, were used for each cleaner. Initial weights were recorded before soiling the coupons on one side with a thin layer using a swab. Dirty weights were taken immediately after soiling, and the coupons were immersed three at a time for five minutes in an unheated (68 F) beaker filled with the respective cleaner. The coupons were air dried before taking final weights and observations.