Amalgam (chemistry) copper trough, which formed a thin coating of mercury on the exterior. The waste ore was then transferred down the trough, and gold in the waste amalgamated with the mercury. This coating would then be scraped off and refined by evaporation to get rid of the mercury, leaving behind somewhat high-purity gold. Mercury amalgamation was first used on silver ores with the development of the patio process in Mexico in 1557. There were also additional amalgamation processes that were created for processing silver ores, including pan amalgamation and the Washoe process. Gold amalgam has proved effective where gold fines ("flour
Dental amalgam controversy safety and effectiveness of amalgam restorations. In 2012, the Australian Dental Association published a position paper on the safety of dental amalgam. Their position is that "Dental Amalgam has been used as a dental restorative material for more than 150 years. It has proved to be a durable, safe and effective material which has been the subject of extensive research over this time" and that "amalgam should continue to be available as a dental restorative material". Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR) is a scientific committee within the European Commission. In a 2008 document of 74