Editing Gangue (section)

==Re-use==
[[Tailings|Waste minerals]] that were once disgarded as gangue are sometimes salvaged and used commercially. For example, in [[copper]] mines in the nineteenth century the mineral [[arsenopyrite]] was dumped until [[arsenic]] compounds became popular as [[insecticide]]s later in the century.

Starting in the second half of the 20th century the environmental benefits of [[recycling]] gangue gained prominence. For example, in 2002, about 130 million tons of gangue were produced per year from [[Mining industry of China#Coal|coal mining in China]]. This, mixed with the 60 million tons of coal mud also produced, could be used for power generation; and the coal mining gangue could be combined with [[coal fly ash]] to produce building materials. The estimated cost of such projects would be up to 4 billion [[Chinese yuan|yuan]], but would be expected to save just over 4 million tons of standard coal per year.<ref>{{cite book| last1 = Murray| first1 = Geoffrey| last2 = Cook| first2 = Ian G.| title = Green China: Seeking Ecological Alternatives| publisher = Routledge| location = New York| year = 2002| pages = 149–150| url = https://www.questia.com/library/102233537/green-china-seeking-ecological-alternatives| access-date = 2017-08-28| archive-date = 2016-03-24| archive-url = https://web.archive.org/web/20160324222248/https://www.questia.com/library/102233537/green-china-seeking-ecological-alternatives| url-status = dead}}</ref>