Reducing Mercury and Increasing Gold in Artisanal Gold MInes

Abstract

Background: Thirty seven percent of global mercury (Hg) pollution stems from small-scale or artisanal gold mining (AGM) usually in impoverished rural communities in developing countries. Small-scale AGM is a main source of income for millions of people. Hg is used to form an amalgam with gold ore and when fired, gold metal remains. We know Hg is toxic to miners, children, waterways and wildlife. There are ways to reduce this pollutionMethods: Forty years ago a small-scale gold miner in Philippines developed a mercury-free gold extraction method, borax, which apart from being nontoxic has two important benefits: it has higher gold-recovery and miners do not need to purchase expensive and toxic Hg. Furthermore,waste tailings from AGM contain high amounts of Hg which slowly evaporates and contributes to global pollution. Appelglobal and partners have developed methods—Peter Plates-- to recover much of the Hg bound gold in the tailings. A byproduct of recovery produces greater amounts of gold – a win-win procedure.Results: The borax Hg-free gold extraction method has positive environmental and health benefits, and has also been shown to recover between 50 to74% more gold than the traditional method. Projects demonstrating Hg-free gold extraction have been carried out in Philippines, Uganda, Mozambique, Mongolia and Peru. In January 2019, a project was carried out in Uganda demonstrating that Hg-free gold extraction required 10 percent longer processing time, but recovered 40% more gold than traditional Hg methods.Conclusion: In contrast with Hg, borax gold mining methods offer clear environmental and worker benefits, and Appelglobal Hg recovery reduces water pollution and increases gold metal recovery. Adopting these methods will benefit informal gold miners and their communities.