Does Glycine Heap Leaching Make <1g/t Gold Deposits Economical Under ESG Pressures?

2025-07-09

Heap leaching with glycine is an emerging technique that could potentially make low-grade gold deposits, such as those with less than 1 gram per ton (g/t), more economically viable, especially under the increasing pressures of environmental, social, and governance (ESG) standards. Here’s a breakdown of how glycine heap leaching could impact the economics and ESG compliance of such projects:

1. Environmental Impact: Glycine is a non-toxic, biodegradable amino acid, making it a more environmentally friendly option than traditional cyanide leaching. This aligns with ESG requirements for reducing environmental harm and improving the sustainability of mining operations.

2. Cost Efficiency: Glycine can selectively leach gold in mild conditions, potentially lowering the costs associated with chemical handling, detoxification, and remediation. If it can achieve sufficient recovery rates, this could improve the economics of processing low-grade ores.

3. Regulatory Compliance: Using glycine can help mining companies meet stringent environmental regulations, which are becoming more common worldwide. This can reduce the risk of regulatory delays, fines, or shutdowns, which are significant concerns under ESG frameworks.

4. Social License to Operate: By adopting more sustainable and less harmful extraction methods, mining companies can improve their relationships with local communities and stakeholders. This can be crucial for maintaining a social license to operate, which is an essential component of ESG considerations.

5. Recovery Rates: The effectiveness of glycine heap leaching for low-grade ores depends on its ability to achieve competitive gold recovery rates. Research and pilot projects are needed to determine its viability and efficiency relative to other methods.

6. Operational Flexibility: Glycine leaching can be integrated into existing heap leaching infrastructure, possibly reducing the capital expenditure needed to switch from cyanide-based processes.

In summary, while glycine heap leaching presents a promising alternative for processing low-grade gold deposits under ESG pressures, its economic feasibility will depend on factors like recovery rates, operational costs, and the specific characteristics of the ore body. Continued research and development, along with pilot testing, will be crucial to fully assessing its potential.