spelter: impure zinc containing about three percent lead and other impurities (especially in the form of ingots)
zinc: a bluish-white lustrous metallic element; brittle at ordinary temperatures but malleable when heated; used in a wide variety of alloys and in galvanizing iron; it occurs naturally as zinc sulphide in zinc blende
poultice: a medical dressing consisting of a soft heated mass of meal or clay that is spread on a cloth and applied to the skin to treat inflamed areas or improve circulation etc.