Polishing Methods There are two types of polishing methods: “acid polishing,” which uses chemicals (a mixture of acids) and traditional “hand polishing,” which uses wooden boards and polishing powder. Satsuma kiriko artisans in Osaka use only hand polishing. Acid polishing dissolves the surface of the glass but doesn’t bring out high quality of its texture and brightness. Hand polishing makes the glass naturally bright and brilliant without damaging the sharp edges of subtle cutwork.