Amalgam (chemistry) miners seeking gold nuggets with the aid of an engine-powered water vacuum mounted on a float. Where stamp mills were used to crush gold-bearing ore to fines, a part of the extraction process involved the use of mercury-wetted copper plates, over which the crushed fines were washed. A periodic scraping and re-mercurizing of the plate resulted in amalgam for further processing. Amalgam obtained by either process was then heated in a distillation retort, recovering the mercury for reuse and leaving behind the gold. As this released mercury vapors to the atmosphere, the process could induce adverse health effects and long
Dental amalgam controversy the use of dental amalgam, but allows phasing down amalgam use over a time period appropriate to domestic needs, an approach advocated by the World Health Organization (WHO). FDI World Dental Federation recognizes the safety and effectiveness of amalgam restorations. FDI is a federation of approximately 200 national dental associations and dental specialist groups representing over 1.5 million dentists. In collaboration with the WHO, they have produced an FDI position statement and WHO consensus statement on dental amalgam. Their position regarding the safety of dental amalgam is that, aside from rare allergic reactions and local side effects, "the small amount