Mercury Free Mining Pilot Program
In late 2021, Mercury Free Mining (MFM), the Alliance for Responsible Mining (ARM), and GIA joined with Peruvian artisanal and small-scale gold miners (ASGM) to launch a new program intended to find alternatives to mercury in gold mining. The partners are bound in recognizing the reliance on artisanal and small-scale gold mining to produce major quantities of an extremely valuable commodity. This situation unfortunately perpetuates the leading cause of anthropogenic mercury pollution. The pilot program aims to proactively develop mercury alternatives in two gold mines, increasing their sustainability, building a traceable ASGM gold supply, and acting as a major leap in the MFM research team’s understanding of how we can ultimately eradicate mercury in gold mining.
Mercury Free Mining, the program lead, is a nonprofit organization founded by Toby Pomeroy, a lifelong goldsmith, jeweler, and passionate advocate for responsible sourcing. Founded in 2019 with the mission of eradicating mercury, MFM has been building a community of jewelers supporting efforts to provide the nearly 20 million ASGM with efficient and nontoxic mercury alternatives where presently unavailable.
MFM’s research and deployment team, led by the author, a geometallurgist, fosters novel sociotechnical solutions to address the issues facing ASGM with a focus on finding suitable mercury alternatives. This is a challenge. Gold is nonreactive to most chemicals (mercury being one of the only exceptions) and coincides with dense black sands that are difficult to mechanically separate (figure 1). The team’s methodologies rely upon the miners’ desire to maximize earnings by recovering more gold from the raw ores while also minimizing harmful social, health, and environmental side effects. Currently, reliable information about implementing mercury alternatives that are more effective and less harmful is scarce. Without this, miners have no choice but to rely upon a multi-generational neurotoxin in order to earn an income (figure 2).
GIA granted $50,000 to jumpstart the pilot. Since then, MFM has collaborated with ARM engineers and Peruvian miners to collect representative mineral samples for use in testing a suite of innovative gold concentrators. MFM is partnering with six mineral processing experts to evaluate their respective technologies based on key performance indicators such as throughput, gold recovery, and concentration ratio. Spread across three continents, the testing will evaluate a large swath of potential mercury alternatives, helping to gather critical information on how different processors are suited for various gold ores (figure 3). This stage of the project will draw from advanced engineering and science to perform thorough analyses in an accurate and timely manner.
Following the testing, the results will be holistically synthesized by the MFM research team with respect to the many complexities of the miners’ unique situations. This will include a mercury comparison to understand the true viability for the miners to adopt an alternative. Stakeholder discussions will then determine whether the miners ultimately decide to adopt one of the mercury-free technologies. If so, the team will help implement the transition to mercury-free methods and conduct observational research to better define the impact on the health of miners and their communities.
The completion of this pilot program in 2022 will mark a turning point in MFM’s ability to minimize the global impacts of mercury by having a tested and verified framework that can translate to additional mercury elimination projects as MFM expands. Following the pilot, the MFM team will publicly release the first report documenting the research process and results in complete detail. This and future reports can be used freely by miners and organizations to enhance the ability to safely source gold. For those interested in learning more, collaborating, or using these methods elsewhere, please contact the author.
