The International Council on Mining and Metals (ICMM) is a CEO-led industry organisation founded in 2001 and headquartered in London, whose membership comprises some of the world's largest mining and metals companies. Its central governance instrument — the ICMM Mining Principles — is a framework of ten overarching principles, supported by position statements, performance expectations, and mandatory reporting requirements, that together define what the organisation considers responsible large-scale mining practice. Although the ICMM's membership roster is dominated by base-metal and precious-metal producers rather than coloured-gemstone houses, the principles have become a meaningful reference point across the broader extractive sector, shaping supply-chain due-diligence expectations for diamonds, rubies, sapphires, emeralds, and other commercially significant gem materials sourced from mechanised or semi-mechanised operations.

Origins and Institutional Context

The ICMM emerged from the Global Mining Initiative, a process launched in 1998 by major mining companies in response to mounting criticism from civil-society organisations, development economists, and environmental bodies regarding the social and ecological costs of large-scale extraction. The initiative commissioned the independent Mining, Minerals and Sustainable Development (MMSD) project, whose 2002 report, Breaking New Ground, provided an evidence base for the governance architecture that the ICMM subsequently developed. Membership is conditional on formal commitment to the Mining Principles and on submission to independent third-party assurance of performance against them — a requirement that distinguishes the ICMM framework from purely aspirational codes.

By the early 2020s, ICMM membership encompassed approximately 26 mining and metals companies and 35 regional and commodity associations. No dedicated coloured-gemstone producer sits among the corporate members, but several diamond producers — most notably De Beers Group (a subsidiary of Anglo American, itself an ICMM member) — operate within the framework's orbit, and the principles are routinely cited in the responsible-sourcing policies of major jewellery retailers and auction houses.

The Ten Principles: Structure and Scope

The Mining Principles, most recently revised in 2020, are organised under three broad thematic pillars: business integrity, people, and planet. Each principle is accompanied by a set of performance expectations that translate the high-level commitment into auditable operational requirements.

• Principle 1 — Ethical business: Members commit to operating with integrity, implementing robust anti-corruption programmes, and adhering to the ICMM's own code of conduct. In the gemstone context, this principle intersects directly with concerns about conflict financing and illicit trade, issues that have been extensively documented in ruby and sapphire supply chains originating in Myanmar and, historically, in diamond supply chains addressed by the Kimberley Process.
• Principle 2 — Governance and reporting: Members must implement management systems aligned with internationally recognised standards and report publicly on sustainability performance, including through the Global Reporting Initiative (GRI) or equivalent frameworks. Transparency of this kind is increasingly demanded by downstream jewellery brands conducting supply-chain due diligence.
• Principle 3 — Human rights: Members are required to respect human rights consistent with the United Nations Guiding Principles on Business and Human Rights (UNGPs). This includes conducting human-rights due diligence, providing access to remedy for affected communities, and avoiding complicity in abuses by state or non-state actors. For the gemstone sector, where artisanal and small-scale mining (ASM) communities are frequently vulnerable to labour exploitation and displacement, this principle carries particular weight even when applied by analogy rather than direct obligation.
• Principle 4 — Community wellbeing: Members commit to contributing to the social, economic, and institutional development of host communities and to avoiding or mitigating adverse social impacts. Community benefit-sharing arrangements and free, prior, and informed consent (FPIC) for indigenous communities are embedded in the associated performance expectations.
• Principle 5 — Workforce: Members must provide safe and healthy workplaces, respect workers' rights to freedom of association and collective bargaining, and prohibit child labour and forced labour. These commitments align with International Labour Organization (ILO) core conventions and are directly relevant to gemstone mining contexts where child labour has been documented, notably in certain tanzanite, ruby, and coloured-sapphire producing regions of sub-Saharan Africa and South and Southeast Asia.
• Principle 6 — Environmental stewardship: Members must identify, assess, and manage environmental risks and impacts across the full mine life cycle, from exploration through to closure and rehabilitation. Specific performance expectations address biodiversity, water stewardship, and tailings management — the last of which gained renewed urgency following the Brumadinho and Mariana tailings dam failures in Brazil between 2015 and 2019.
• Principle 7 — Climate change: Members commit to managing greenhouse-gas emissions, setting science-based reduction targets, and disclosing climate-related risks in line with the Task Force on Climate-related Financial Disclosures (TCFD) framework. While gemstone mining is a relatively minor contributor to global emissions compared with iron-ore or coal extraction, the principle establishes a benchmark that responsible-sourcing frameworks in the jewellery sector increasingly reference.
• Principle 8 — Water: Members must implement water-stewardship practices that protect water quality and quantity for ecosystems and communities. Gemstone mining — particularly alluvial operations for sapphires, rubies, and spinels — can significantly alter watercourses and affect downstream agricultural and domestic water users, making this principle relevant beyond the ICMM's immediate membership.
• Principle 9 — Biodiversity and land: Members commit to a mitigation hierarchy — avoid, minimise, restore, offset — in managing impacts on biodiversity and ecosystems, and to contributing to a net-positive impact on biodiversity where feasible. Several significant gemstone deposits lie within or adjacent to areas of high conservation value, including ruby and sapphire deposits in Madagascar and spinel localities in the Eastern Arc mountains of Tanzania.
• Principle 10 — Mine closure: Members must plan and finance responsible mine closure from the outset of operations, ensuring that sites are left in a condition that does not pose unacceptable risks to communities or the environment. In the artisanal gemstone sector, the absence of closure planning is a persistent problem, with abandoned pits creating hazards and disrupting land use for decades after mining ceases.

Assurance and Verification

A defining feature of the ICMM framework — and one that distinguishes it from many voluntary codes in the extractive sector — is its mandatory independent assurance requirement. Member companies must have their sustainability reports assured by an accredited third party against the ICMM's assurance procedure, which is aligned with the International Standard on Assurance Engagements (ISAE) 3000. The assurance process covers both the accuracy of reported data and the adequacy of underlying management systems.

This architecture of external verification has influenced the design of responsible-sourcing standards in the jewellery sector. The Responsible Jewellery Council (RJC), whose Code of Practices is the most widely adopted certification standard in the jewellery supply chain, incorporates requirements drawn from or aligned with ICMM principles, and requires third-party certification audits of member companies. The Gemological Institute of America (GIA) and other gemmological laboratories have increasingly engaged with provenance and responsible-sourcing questions, though laboratory reports do not themselves constitute supply-chain audits.

Relevance to the Coloured-Gemstone Sector

The ICMM's direct membership does not include artisanal or small-scale mining (ASM) operators, who account for the overwhelming majority of coloured-gemstone production globally — estimates from the World Bank and sector researchers consistently place ASM's share of coloured-gemstone output at 70 to 80 per cent or above. This structural gap means that the ICMM framework cannot be applied wholesale to the gemstone supply chain. Nevertheless, its influence operates through several indirect channels.

First, large-scale mechanised gemstone operations — including certain tanzanite mines in Tanzania, some emerald operations in Zambia and Brazil, and diamond mines operated by ICMM-affiliated companies — are directly subject to or voluntarily adopt the principles. Gemfields Group, the London-listed producer of Zambian emeralds and Mozambican rubies, is not an ICMM member but has adopted sustainability reporting frameworks and community-development commitments that parallel ICMM expectations, reflecting the normative influence of the principles on the sector.

Second, downstream jewellery brands and retailers that source from both large-scale and artisanal operations increasingly use ICMM-aligned criteria as a baseline when constructing their own supplier codes of conduct and due-diligence questionnaires. The principles thus function as a reference standard even for supply chains that fall outside the ICMM's formal jurisdiction.

Third, the ICMM's engagement with the ASM sector — through its position statement on artisanal and small-scale mining, which calls on members to engage constructively with ASM communities operating near or within their concessions — has practical implications for gemstone localities where large-scale and artisanal operations coexist, such as the ruby and sapphire fields of Mozambique and Madagascar.

Limitations and Criticisms

The ICMM framework has attracted substantive criticism from civil-society organisations, academic researchers, and affected communities. Several recurring concerns are relevant to the gemstone sector.

The voluntary nature of membership means that the most problematic operators — those most likely to cause environmental damage or human-rights abuses — have no incentive to join and are entirely outside the framework's reach. In the gemstone sector, this limitation is acute: the mines producing the most commercially significant coloured stones are frequently located in jurisdictions with weak regulatory capacity, and the operators most in need of governance frameworks are precisely those least likely to adopt them voluntarily.

Critics have also questioned the rigour of the assurance process, noting that third-party assurers are engaged and paid by the companies being assured, creating potential conflicts of interest analogous to those that have been identified in financial auditing. The ICMM has responded by tightening its assurance procedure over successive revisions, but the structural tension remains.

Finally, the principles' emphasis on large-scale, formally organised mining operations means that they offer limited practical guidance for the governance of ASM — a gap that is particularly significant for coloured gemstones. Initiatives such as the Alliance for Responsible Mining (ARM) and its Fairmined standard, and the Artisanal Gold Council's work on formalisation, address this gap more directly, though they operate at a much smaller scale and with fewer resources than the ICMM.

The 2020 Revision and Current Trajectory

The 2020 revision of the Mining Principles was the most comprehensive update since the framework's inception. Key changes included the elevation of climate change to a standalone principle (previously addressed within the environmental principle), the strengthening of human-rights due-diligence requirements to align with the UNGPs, and the introduction of more prescriptive performance expectations to reduce ambiguity in assurance. The revision also placed greater emphasis on the concept of a social licence to operate — the informal acceptance of a mining operation by host communities and civil society — as a business-critical asset rather than a peripheral concern.

Looking forward, the ICMM has signalled increasing engagement with nature-related financial disclosures, aligned with the Taskforce on Nature-related Financial Disclosures (TNFD), and with the post-2020 Global Biodiversity Framework adopted at COP15 in Montreal in 2022. For the gemstone sector, these developments are consequential: several of the world's most biologically significant landscapes — the Eastern Arc mountains, the rainforests of Madagascar, the highlands of Myanmar — are also among its most important gem-producing regions, and the pressure on companies to account for biodiversity impacts is intensifying.

Practical Implications for Gem-Trade Professionals

For gemmologists, jewellery buyers, and supply-chain professionals, the ICMM principles function less as a direct compliance requirement and more as a benchmark against which responsible-sourcing claims can be evaluated. When a mining company or gemstone producer asserts that its operations meet international sustainability standards, familiarity with the ICMM framework provides a basis for assessing the substance of that claim. Key questions include whether the operation is subject to independent third-party assurance, whether it reports publicly against a recognised sustainability framework, and whether its community-engagement and environmental-management practices align with the performance expectations embedded in the principles.

The principles also provide a useful vocabulary for supply-chain due-diligence conversations. Concepts such as the mitigation hierarchy, free prior and informed consent, and human-rights due diligence — all embedded in the ICMM framework — are increasingly standard in responsible-sourcing discourse and are referenced in the due-diligence guidance issued by the Organisation for Economic Co-operation and Development (OECD) for mineral supply chains.

Further Reading

• ICMM Mining Principles — official framework documentation (icmm.com)
• Responsible Jewellery Council — Code of Practices (responsiblejewellery.com)
• OECD Due Diligence Guidance for Responsible Supply Chains of Minerals from Conflict-Affected and High-Risk Areas (oecd.org)
• GIA Gems & Gemology — Responsible Sourcing of Coloured Stones (gia.edu)