Zimbabwe Pushes Mercury-Free Gold Mining as Government Tests Safer Processing Technologies

MAZOWE, Zimbabwe – The Government has intensified efforts to eliminate the use of mercury in artisanal and small-scale gold mining, with officials conducting assessments of alternative gold processing technologies aimed at protecting miners, communities, and the environment.

The initiative forms part of Zimbabwe's broader drive to promote sustainable mining practices while improving gold recovery rates among small-scale miners, who contribute a significant share of the country's annual gold output. This week, officials from the Department of Metallurgy under the Ministry of Mines and Mining Development, the Environmental Management Agency (EMA), and the Planet Gold Zimbabwe Project visited mining operations in Mashonaland Central Province to evaluate potential sites for mercury-free processing centres.

The assessment focused on Kuzivakwashe Mining Syndicate in Mazowe District and Chiweshe Rosa Mine, where technical teams are collecting baseline data and evaluating the suitability of cleaner gold extraction methods.

Department of Metallurgy official Reginald Chidawanika said the exercise is part of a national programme aimed at developing and deploying affordable mercury-free gold processing technologies for small-scale miners.

"The primary one is the leaching and precipitation method, where we use ordinary bleach and hydrochloric acid. When they are mixed together, they release chlorine gas, which dissolves the gold," said Chidawanika.

"When the gold gets into solution, we can separate the gold-bearing solution from the siliceous gang material through filtration. After recovering the solution, the gold can then be reprecipitated using sodium metabisulfite."

The process eliminates the need for mercury while maintaining effective gold recovery rates.

Chidawanika said a second method is being considered for ore containing coarse-grained gold, which can be recovered through gravity concentration techniques. Under this system, miners mill ore and recover concentrates using conventional gravity equipment before further processing through technologies such as Falcon concentrators, Nelson concentrators, or Gemini tables.

"After recovering the gold, it can be taken straight for smelting," he said.

For miners dealing with ore that contains limited free gold, authorities are also assessing cyanidation and other leaching technologies that do not require mercury. Officials believe these methods can improve gold recovery while reducing environmental contamination and health risks associated with mercury exposure.

According to Chidawanika, the proposed technologies are designed to remain accessible to artisanal and small-scale miners. He said the methods rely on readily available reagents and relatively simple processing equipment, making them suitable for widespread adoption across Zimbabwe's gold-producing districts.

As part of the assessment programme, ore samples from selected mining sites have been sent to accredited laboratories in South Africa for detailed metallurgical testing and technical recommendations.

"I would like to think that by year-end we would have established some of these methods at some of our small-scale mines because we are now at the stage of developing mercury-free technologies," Chidawanika said.

Planet Gold Zimbabwe Project Manager Nyaradzo Mutonhori said the initiative is expected to reduce mercury consumption within the small-scale mining sector significantly. The project aims to cut mercury use by approximately 4.85 tonnes over the next five years, helping Zimbabwe align with global efforts to reduce mercury pollution and promote responsible gold mining. Mining experts say successful adoption of mercury-free processing technologies could improve environmental protection, strengthen occupational safety, and enhance the long-term sustainability of Zimbabwe's rapidly growing artisanal and small-scale gold mining industry.

Mercury-free gold mining Zimbabwe