Metal (or their alloys) with relatively low melting points. Such metals include zinc, cadmium, tin, antimony (here counted as a metal), lead, and bismuth, some of which are quite toxic. In Britain, the fine art trade uses the term "white metal" in auction catalogues to describe foreign silver items which do not carry British Assay Office marks, but which are nonetheless understood to be silver and are priced accordingly. A heavy metal is any relatively dense metal or metalloid. More specific definitions have been proposed, but none have obtained widespread acceptance. Some heavy metals have niche uses, or are notably toxic;
Metal and Machinery Workers Industrial Union Reuther Library in Detroit. Metal and Machinery Workers Industrial Union The Metal and Machinery Workers Industrial Union No. 440 (MMWIU) was a labor union in the United States which existed between 1907 and 1950. It organized workers in the manufacturing industry and was affiliated with the Industrial Workers of the World (IWW). The earliest recorded local of the MMWIU was in Bridgeport, Connecticut in 1907. A number of machinists' locals were also active under the IWW around that time, which dated from a period when a large number of craft union locals were switching their affiliation to the IWW, and