23 diciembre 2014
Nearly 20 percent of the world’s gold supply is produced by workers in artisanal and small-scale gold mining shops that purify gold by burning off mercury. Researchers have teamed up to stop this mercury where it starts.
http://feeds.sciencedaily.com/~r/sciencedaily/~3/2n3W-A6qZgM/141223113823.htm
