JORC and NI 43-101 Resource Reports Explained
A resource report is the document buyers rely on most and scrutinise least. This guide explains the reporting codes in the CRIRSCO family — JORC, NI 43-101, SAMREC, PERC and S-K 1300 — the difference between a resource and a reserve, why the competent or qualified person matters more than the tonnage headline, and the specific red flags that distinguish a weak report from a fabricated one.
The Reporting Codes and Why They Exist
Mineral reporting codes exist because the value of a mining asset rests on an estimate of material nobody can see. Without a common standard, tonnage figures are marketing. The codes impose a structure: who may report, on what basis, and with what disclosure.
The CRIRSCO family
| Code | Jurisdiction | Responsible professional |
|---|---|---|
| JORC Code | Australasia | Competent Person |
| NI 43-101 | Canada | Qualified Person |
| SAMREC | South Africa | Competent Person |
| PERC | Europe | Competent Person |
| S-K 1300 | United States (SEC) | Qualified Person |
These standards are broadly aligned through CRIRSCO, so the categories translate reasonably well between them. What differs is the regulatory force: a report filed to satisfy a stock-exchange listing requirement carries consequences for its author that a private report prepared for a bilateral sale does not.
Public versus private reports
Most reports shown in private mining-asset transactions were never filed with an exchange or regulator. They may still be entirely proper — but nobody has reviewed them, and the sanction for overstatement is weaker. Ask directly whether the report was publicly filed, and if so, obtain it from the exchange or regulator rather than from the vendor.
Resources, Reserves and Why the Split Matters
The single most common misreading of a resource statement is treating the total tonnage as the asset. The distribution across confidence categories carries most of the information.
Resource categories, by increasing confidence
- Inferred — geological evidence sufficient to imply but not verify continuity. Cannot be converted to a reserve and should not be used in economic studies.
- Indicated — confidence sufficient to support a pre-feasibility study and convert to a probable reserve.
- Measured — highest confidence; may convert to a proved reserve.
Reserves
A reserve is the economically mineable portion, established after applying modifying factors: mining method and dilution, metallurgical recovery, infrastructure, capital and operating cost, commodity price, permitting, and legal access to the ground. A resource with no reserve is not necessarily a poor asset — it is an earlier one.
Reading the table properly
Look for the cut-off grade and the price assumption behind it, the effective date, whether the estimate is reported inclusive or exclusive of reserves, and the contained metal rather than only tonnes and grade. A large tonnage at a marginal grade with a high price assumption behaves very differently from a smaller, higher-grade estimate.
The Competent Person Is the Report's Real Signature
Codes work by attaching personal professional accountability to the estimate. If nobody has taken that responsibility, the document is not a code-compliant report whatever its cover page says.
What to confirm
- The competent or qualified person is named, with their professional organisation and membership number.
- Their experience is relevant to the deposit type and to the activity reported — resource estimation is a different competency from mine engineering.
- Written consent to the inclusion of their statements appears in the report.
- Their independence, or the absence of it, is disclosed.
Verify the person, not just the paper
Professional bodies maintain public membership registers. Checking a name against the register takes minutes and detects one of the more common forms of technical-report fraud: a real report attributed to a person who never worked on it, or a fabricated professional identity. Contacting the named person directly, using contact details you obtain independently rather than from the report, is a reasonable step on a material transaction.
Red Flags in a Technical Report
Fabricated and inflated reports circulate widely in private mining-asset offers, particularly for gold and critical minerals. Most share recognisable characteristics.
| Red flag | What it suggests | How to test it |
|---|---|---|
| No named competent person | Not code-compliant | Require a name, membership and consent |
| Headline tonnage, no categories | Estimate may not exist | Request the full classified table |
| No effective date | Figures may be stale or invented | Require date and effective date |
| Tenement numbers absent or mismatched | Report may relate to other ground | Reconcile against the register extract |
| No QA/QC or laboratory detail | Assays unverifiable | Request lab name, accreditation, standards and blanks |
| Coordinates outside the tenement | Data borrowed from another project | Plot collars against tenement boundaries |
| Grades far above deposit-type norms | Possible salting or selective reporting | Benchmark against comparable deposits |
The assay chain
Assay certificates are the most frequently forged documents in mining transactions. Request them directly from the laboratory where possible, confirm the laboratory is accredited, and look for the quality-control data that any competent programme produces: certified reference standards, blanks and duplicates. A sample set with no quality-control data is not evidence of grade.
Putting the Report in Commercial Context
A technically sound report tells you what is in the ground. It does not tell you whether the transaction is sound.
What a report never covers
- Whether the vendor holds the tenement, or has authority to sell it.
- Encumbrances, third-party royalties and pre-existing farm-in rights.
- Rehabilitation liability attaching to the ground.
- Native title, heritage and access agreements.
- Whether the tenement can lawfully be transferred to you, and on what conditions.
Those sit in title and counterparty diligence, covered in our tenement due diligence checklist. A flawless resource statement over ground the seller does not control is worth nothing, and that combination is more common than a fabricated orebody.
Lodfy confirms the entity, maps beneficial ownership, screens against sanctions lists and validates trade and corporate documents before you commit funds.
Verify a counterpartyFrequently Asked Questions
What is the difference between a mineral resource and an ore reserve?
A mineral resource is a concentration of material with reasonable prospects for eventual economic extraction. An ore reserve is the economically mineable part of a resource, established through at least a pre-feasibility study that applies modifying factors such as mining method, processing recovery, infrastructure, costs, permitting and legal access. Only indicated and measured resources can convert to reserves; inferred resources cannot. A project quoting a large resource and no reserve has not yet demonstrated economic viability.
What are the resource and reserve categories?
Resources are classified by increasing geological confidence as inferred, indicated and measured. Reserves are classified as probable and proved, derived from indicated and measured resources respectively. The distribution across categories matters more than the total: a headline tonnage that is almost entirely inferred represents a far earlier and more speculative stage than the same tonnage reported as measured.
Who is a competent person or qualified person?
A competent person under JORC, or a qualified person under NI 43-101, is a named professional with defined minimum experience relevant to the deposit type and the activity being reported, who belongs to a recognised professional organisation and takes personal responsibility for the disclosure. Their name, membership and consent should appear in the report. An unsigned report, or one attributed only to a company, does not comply with the code it claims to follow.
How can I tell if a JORC report is fake?
Check whether a named competent person is identified with professional membership and written consent, and verify that membership directly with the professional body. Confirm the tenement numbers in the report match the current register extract. Look for the assay laboratory, its accreditation and quality-control data. Be sceptical of reports quoting only headline tonnage without categories, lacking a date and effective date, or with drill collar coordinates that do not plot within the tenement boundaries.
Does a JORC or NI 43-101 report guarantee the deposit is economic?
No. A compliant resource statement is a disclosure of geological confidence prepared to a standard; it is not a valuation and not a guarantee of economic extraction. Even a reserve, which does incorporate economic assumptions, depends on the commodity price, cost and recovery assumptions used at the effective date. Always read the assumptions and the sensitivity analysis rather than the headline number.