If you follow mining stocks listed on the Australian Securities Exchange — known as the ASX — you will regularly encounter the phrase “JORC compliant” in company announcements, resource estimates, and technical reports. It appears so frequently that many investors simply skip over it. But understanding what the JORC Code actually is, and what it guarantees — and does not guarantee — is fundamental to reading any Australian mining company’s disclosures accurately.
This guide explains the JORC Code in plain language, from what it is and why it exists, to how it classifies mineral resources and what it means in practice for investors.
The Short Answer
The JORC Code is Australia’s mandatory professional standard for reporting mineral exploration results, resources, and reserves. It is built into the ASX’s listing rules and must be followed by all ASX-listed mining companies when making public statements about their mineral projects.
Why Was the JORC Code Created?
Like Canada’s NI 43-101, the JORC Code was born from the fallout of a major mining scandal — in this case, the Poseidon nickel boom and bust of the late 1960s.
In 1969, a small Western Australian company called Poseidon NL announced a significant nickel discovery at Windarra in Western Australia. News of the find — coupled with a global surge in nickel demand driven by the US space program — sent the company’s share price from around $1 to over $280 in a matter of months. Investors poured money in based almost entirely on unverified exploration reports with no standardised basis for comparison. When the deposit failed to deliver on its extraordinary promise and nickel prices collapsed, the stock crashed and billions in speculative value evaporated.
In response to the chaos and the evident lack of professional standards in mining disclosure, the Australian Mining Industry Council — now the Minerals Council of Australia — established a committee to examine the issue. The result was the first edition of what became known as the JORC Code, developed through the Joint Ore Reserves Committee. The current edition, the 2012 JORC Code, came into mandatory operation on December 1, 2013, and remains the governing standard today.
In August 2024, the Australasian Joint Ore Reserves Committee released a draft revised JORC Code for public consultation, which closed in October 2024. As of the time of writing, an updated edition has not yet been formally adopted. Investors and companies should monitor the JORC website at jorc.org for the latest status of any revisions.
Who Maintains the JORC Code and Who Must Follow It?
The JORC Code is produced and maintained by the Australasian Joint Ore Reserves Committee, which represents three peak bodies: the Australasian Institute of Mining and Metallurgy (AusIMM), the Australian Institute of Geoscientists (AIG), and the Minerals Council of Australia.
The Code forms part of the ASX Listing Rules — specifically Chapter 5 of those rules — which means it is not optional for ASX-listed mining companies. Any company listed on the ASX that makes a public statement about mineral exploration results, resources, or reserves must do so in accordance with the JORC Code. Failure to comply is a breach of the ASX Listing Rules and can trigger regulatory action by both the ASX and the Australian Securities and Investments Commission (ASIC).
The JORC Code also applies to exploration and mining companies listed in New Zealand and Papua New Guinea through their respective exchanges. It is increasingly used internationally as a reference standard by companies in other jurisdictions that lack their own equivalent framework.
The Competent Person — The JORC Equivalent of a Qualified Person
The core concept behind the JORC Code — just like Canada’s NI 43-101 — is that all public technical disclosures must be prepared or signed off by an independent, credentialed expert. Under JORC, this person is called the Competent Person, abbreviated as CP.
To qualify as a Competent Person under the JORC Code, an individual must:
- Hold a recognised professional qualification — typically membership or fellowship of AusIMM or AIG, or a recognised overseas equivalent organisation that enforces a professional code of ethics and has disciplinary powers.
- Have at least five years of relevant experience in the specific style of mineralisation or type of deposit being reported on. Experience in gold exploration does not qualify someone to sign off on a lithium brine resource, for example.
- Take overall responsibility for the report — the CP’s name must be included in any public disclosure, along with their professional organisation and a confirmation that the report meets JORC requirements.
The requirement for individual accountability is one of the JORC Code’s most important investor protections. If a Competent Person signs off on a report that is later found to contain misleading information, they face professional disciplinary action from their industry body — not just regulatory action against the company.
Think of the Competent Person as the auditor of a mining company’s geological claims. They put their professional reputation and credentials on the line every time they sign off on a public disclosure.
The Three Governing Principles
The JORC Code is built around three governing principles that apply to all public reports:
- Transparency — public reports must include all information that investors and their advisers would reasonably need to make an informed assessment. Material information cannot be selectively omitted.
- Materiality — only information that is material to an investor’s decision needs to be disclosed, reducing the risk of drowning important data in irrelevant detail.
- Competence — all reports must be prepared by or under the supervision of a Competent Person with relevant experience.
Resource and Reserve Classification — What the Numbers Mean
The JORC Code establishes the same three-level resource classification system used by NI 43-101, based on how much data has been collected and how confident geologists are in the estimate:
- Inferred Resource — the lowest confidence level. Based on limited data, typically from a small number of drill holes. The deposit’s existence is reasonable to assume but not well-defined. Think of it as: something is likely here but we haven’t confirmed it properly yet.
- Indicated Resource — a higher confidence level. Supported by more substantial drilling and sampling. The size, grade — meaning the concentration of the metal or mineral — and continuity of the deposit can be estimated with reasonable confidence. Think of it as: we have a solid picture of what is here.
- Measured Resource — the highest confidence level. Based on close-spaced, detailed data collection. The deposit is well enough understood to support detailed mine planning. Think of it as: we know precisely what is here.
Mineral reserves — the portion of a resource that has been shown to be economically mineable through detailed engineering studies — are further classified as either Probable (based on Indicated resources) or Proved (based on Measured resources). These are the numbers that ultimately underpin a mine’s production plan and financial projections.
Under JORC, inferred resources cannot be used as the basis for economic analysis or mine planning. This is a fundamental protection against the kind of speculative inflation that destroyed investor wealth in the Poseidon era.
Table 1 — The Practical Backbone of JORC Reporting
A practical feature of the JORC Code that investors should be aware of is the requirement for companies to complete a disclosure checklist known as Table 1 whenever they publish exploration results or resource estimates. Table 1 is a standardised template covering all the material criteria relevant to the type of disclosure being made — sampling methods, drill hole spacing, data quality checks, and so on.
When a company publishes a JORC-compliant announcement, Table 1 is usually attached as an appendix. It may look dry, but it is actually one of the most useful tools available to investors — it shows exactly what information the Competent Person considered and how transparent the company is being about its methodology. A well-completed Table 1 is a positive signal. A vague or incomplete one warrants scrutiny.
JORC and the Rest of the World
Although the JORC Code is an Australian standard, its influence extends well beyond the ASX. It is accepted by the London Stock Exchange and Hong Kong Stock Exchange as a valid basis for mining property disclosure. Many non-Australian companies use JORC as their reporting framework even where it is not legally required, simply because it is internationally recognised.
For companies dual-listed on the ASX and TSX in Canada, JORC and NI 43-101 reports are generally considered interchangeable for the purposes of satisfying both regulatory bodies. Both standards are members of CRIRSCO — the Committee for Mineral Reserves International Reporting Standards — which aligns the core definitions and classification frameworks across all major mining codes globally.
What JORC Does NOT Guarantee
JORC compliance means the technical information has been prepared and reviewed to a recognised professional standard. It does not mean the project is economically viable, that it will become a mine, or that it is a good investment. Always conduct your own research.
A JORC-compliant resource estimate gives investors a reliable, standardised picture of what a Competent Person believes is in the ground. Whether that resource can be profitably extracted depends on many other factors — ore grades, commodity prices, processing costs, permitting timelines, management capability, and available capital — none of which JORC addresses.
Key Takeaways for Investors
- The JORC Code is mandatory for all ASX-listed mining companies under ASX Listing Rules Chapter 5
- It was developed in response to the Poseidon nickel bubble and bust of the late 1960s
- All technical disclosures must be prepared or approved by a Competent Person — a credentialed, independently accountable expert
- Resource classifications — Inferred, Indicated, Measured — reflect confidence levels in the geological data
- Table 1 is attached to JORC announcements and shows the methodology behind the data
- JORC is accepted internationally and recognised alongside NI 43-101 and SEC S-K 1300 as a world-class standard
- JORC compliance does not guarantee a project is economically viable or a sound investment
SOURCES
1. JORC Code 2012 Edition — jorc.org: https://www.jorc.org/docs/jorc_code2012.pdf
2. JORC Code overview and history — jorc.org: https://www.jorc.org
3. ASX Listing Rules Chapter 5 and Guidance Note 31 — asx.com.au: https://www.asx.com.au/regulation/rules-guidance-notes-and-waivers/asx-listing-rules.htm
4. K&L Gates — JORC Code Update: https://www.klgates.com/JORC-Code-Update-9-28-2023
5. National Law Review — Australia Updates JORC Code: https://natlawreview.com/article/jorc-code-update
6. Mining.com.au — How JORC Reporting Works in Australia: https://mining.com.au/how-jorc-reporting-works-in-australia/
7. Geology for Investors — Decoding the JORC Code: https://www.geologyforinvestors.com/decoding-the-jorc-code-an-overview-for-investors/
DISCLAIMER
This article is an educational explainer based on publicly available regulatory documents, professional standards documentation, and published industry sources. Information was current as of May 2026. The JORC Code is subject to periodic revision — readers should consult jorc.org and ASX Listing Rules for the most current requirements.
Mining Markets Report has not received compensation from any company, regulatory body, or organisation in connection with this article.
The information provided is for informational and educational purposes only and does not constitute financial, investment, legal, or professional advice. Readers are encouraged to conduct their own due diligence and consult a qualified professional before making any investment decision.
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