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Concentration of Gold Ores - a Key to Reducing Mercury Use in Artisanal and Small Scale Gold Mining

In artisanal gold mining, mercury is essentially used to concentrate the gold. It does this by bonding with the gold to form a heavy amalgam that is then easily separated from the other minerals. It follows therefore, that if mercury is used as a mechanism of concentration, producing concentrates of gold ores through other means can enable reduction or even elimination of mercury use. In other words, a good process of concentration can replace mercury and lead to big environmental and health improvements.
Concentrating gold ores before applying mercury greatly reduces the mass of material that comes into contact with mercury. This reduces the amount of material that becomes contaminated and also the amount of mercury that is required to be applied. And of course, if concentration is done with sufficient sophistication and knowledge, mercury is not needed at all.
As an important first step along the way to eliminating mercury, concentrating avoids a worst practice called whole-ore-ama…

Is Borax the Miracle Chemical that Will Replace Mercury in Artisanal Gold Mining?

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The Myth of a Miracle Cure

Can borax replace mercury in artisanal gold mining? – or is it better concentration that can replace mercury? Does Borax really have anything to do with it?

Is Borax a Miracle Chemical?

Those promoting borax as a replacement for mercury in small scale gold mining are overselling it and risk giving the impression that there is a miracle cure. They may be well intentioned but they are misleading the world by claiming that borax is a direct replacement for mercury. This is simply not true.

The bar of gold shown here was entirely produced using borax. It was also entirely produced using mercury. How can that be if the word going around is that borax is a replacement for mercury?


It is not. Borax is used in every Artisanal and Small Scale Mining gold shop in the world and has been for a hundred years. It has been used in pottery glazes for centuries for the same reason. It is a flux.
Background: if a miner has 10 kilograms of sand that contains 10 grams of gold, t…

Health and Artisanal Gold Mining

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By Dr. Paleah Moher, Human and Ecosystem Health, AGC
Artisanal and Small-scale Gold Mining (ASGM) presents a complex development and health-impact situation. On one hand it provides livelihoods to tens of millions people in the developing world while contributing significantly to the global supply of gold.  On the other hand ASGM is accompanied by serious environmental, social and health concerns. Here we discuss the health concerns and their solutions.
Generally sustainable solutions support the ASGM sector’s economy while also addressing the associated health problems. This can be realized through inexpensive safer mining practices that come along with increasing degrees of education and formalisation. Fortunately there are often economic incentives to drive such improvements.
Mercury is one of the main health concerns of ASGM. The use of mercury to amalgamate and extract metals from rock has been in practice for over 5000 years , mainly because it is a simple, expedient, and relativ…