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 expansion and contraction of the various amalgam products. During the American Civil War, the debate on the merits of amalgam continued. In dental meetings, with now decades of use and dental research came the recognition of the importance of good technique and proper mixture on long-term success. It was argued that, "the fault was not in the material but in the manipulation...Some men's amalgam is good universally, and some men's gold is bad universally; the difference lies in the preparation of the tooth and in the plug (filling)." More controversy came in 1872, when an amalgam filling was reported as