How to Read an NI 43-101 Technical Report: The 27 Items and Which Ones Matter

Summary box

• A technical report follows Form 43-101F1, a fixed table of contents. Every report has the same skeleton, which makes them directly comparable once you know the structure.
• A Qualified Person needs a relevant degree, at least five years of relevant experience, experience relevant to this project, and good standing with a recognised professional association.
• Certain disclosure triggers a filing obligation within 45 days.
• The high-signal items are 11, 12, 13, 14, 15, 22 and 25. The rest is largely context.
• Item 25 — the QP's own interpretation and conclusions — is where the report tells you what it actually thinks. Most readers never get there.

Why the format is the point

Every NI 43-101 technical report is written to the same template: Form 43-101F1. That standardisation is the document's most useful property. Once you know where the recovery assumptions live, you can find them in any report, from any issuer, in any jurisdiction that accepts the instrument.

The structure runs, in order: summary; introduction; reliance on other experts; property description and location; accessibility, climate, local resources, infrastructure and physiography; history; geological setting and mineralization; deposit types; exploration; drilling; sample preparation, analyses and security; data verification; mineral processing and metallurgical testing; mineral resource estimates; mineral reserve estimates; mining methods; recovery methods; project infrastructure; market studies and contracts; environmental studies, permitting and social or community impact; capital and operating costs; economic analysis; adjacent properties; other relevant data and information; interpretation and conclusions; recommendations; and references.

Reports on properties without reserves omit or abbreviate several of the development-stage items. That omission is itself a signal about project stage.

Who is allowed to write it

The instrument defines a qualified person as an individual who:

"(a) is an engineer or geoscientist with a university degree, or equivalent accreditation, in an area of geoscience, or engineering, relating to mineral exploration or mining; (b) has at least five years of experience in mineral exploration, mine development or operation, or mineral project assessment, or any combination of these, that is relevant to his or her professional degree or area of practice; (c) has experience relevant to the subject matter of the mineral project and the technical report; (d) is in good standing with a professional association..."

Two of those four conditions are routinely glossed over. Condition (c) is project-specific: a QP with thirty years in porphyry copper is not automatically qualified to sign off a spodumene pegmatite metallurgical section. And the professional association must be one that, among other things, requires compliance with professional standards of competence and ethics and "has and applies disciplinary powers, including the power to suspend or expel a member."

Where independence is required, the instrument sets a defined test rather than leaving it to judgment. Check who signed each section, what their affiliation is, and whether the independence certificate is present.

The filing trigger and the 45-day clock

Filing a technical report is not optional or discretionary once certain disclosure is made. Where the obligation is triggered, the instrument requires the issuer to file the report within 45 days of the disclosure — earlier if a preliminary short-form prospectus or a directors' circular is involved. The issuer must also "issue a news release at the time it files the technical report disclosing the filing of the technical report and reconciling any material differences in the mineral resources or mineral reserves" versus what was previously disclosed.

That reconciliation requirement is a gift to the careful reader. When a company announces a resource update by press release and then files the report, the news release accompanying the filing must explain material differences. Read both.

The seven items that carry the risk

Item 11 — Sample preparation, analyses and security. Where the chain of custody breaks, everything downstream is suspect. Look for certified reference materials, blanks, duplicates, insertion rates, and whether failures were investigated and re-assayed. This section is where the historical mining frauds would have been caught.

Item 12 — Data verification. The QP must state what they personally checked and what they took on trust. Read the limitations paragraph. "The QP was unable to verify historical drilling from the 1980s" is a materially different report from one where the QP twinned holes and re-assayed pulps.

Item 13 — Mineral processing and metallurgical testing. Recovery is the largest single swing factor in project economics after grade and price, and it is where optimistic assumptions hide most comfortably. Look for: how many samples were tested; whether they are spatially representative of the deposit or drawn from the best zone; whether variability testwork was done, not just composite testwork; whether deleterious elements (arsenic, antimony, mercury, uranium, chlorine, magnesium) were assessed; and whether the recovery used in the economic model is supported by the testwork or extrapolated beyond it.

Item 14 — Mineral resource estimates. Category split, cut-off grade, metal price assumption, capping or top-cutting of high assays, block model parameters, search ellipse, and the statement of reasonable prospects for eventual economic extraction. Confirm whether resources are reported inclusive or exclusive of reserves.

Item 15 — Mineral reserve estimates. Present only where a Pre-Feasibility Study or better exists. Check the Modifying Factors and the dilution and mining recovery assumptions. Planned dilution of 5% on a narrow-vein underground deposit is optimistic; 15–20% is closer to typical.

Item 22 — Economic analysis. NPV, IRR, payback, discount rate, metal price deck, and — crucially — the sensitivity tables. The base case is a marketing number. The sensitivities tell you how the project behaves in the world that actually occurs. Look at NPV at spot minus 20%, and at capex plus 25%.

Item 25 — Interpretation and conclusions. The QP's own view, in their own words, including risks and uncertainties. It is short, it is candid relative to the rest of the document, and it is the last thing most readers reach. Read it first.

Reading the economics without being anchored

The economic analysis section will lead with a base case. Before you absorb it:

1. Check the metal price deck against spot and consensus. A gold project modelled at a price well above the prevailing spot price is a leveraged bet on the price, not a mining investment.
2. Check whether NPV is pre-tax or post-tax. Pre-tax NPV is systematically larger and much less relevant. Reports typically disclose both; headlines often quote the friendlier one.
3. Check the discount rate. 5% is common for gold, 8% for base metals, but the choice is a judgment. A jurisdiction-risk-adjusted rate for a frontier-market project ought to be higher than for a Nevada project, and often is not.
4. Check what capex includes. Initial capex, sustaining capex, closure costs and contingency are separate lines. Contingency below 10% on a pre-feasibility-level estimate is thin.
5. Check the accuracy band. A PEA estimate is typically ±30–50%; a PFS ±20–30%; a Feasibility Study ±10–15%. Compare that band against the project's NPV margin. If a 20% capex overrun eliminates the NPV, the study has not demonstrated viability, it has demonstrated fragility.

The document is dated the moment it is filed

An effective date is not a formality. Between the effective date and the day you are reading, the deposit may have been depleted by mining, metal prices have moved, costs have inflated, and permits have advanced or stalled. A five-year-old feasibility study on a producing mine is a historical document.

Check whether a more recent estimate exists in a subsequent annual information form, 10-K, 20-F or annual report. Companies update reserve and resource statements more often than they file full technical reports, and the shorter disclosures are frequently more current.

The equivalents elsewhere

If you work across exchanges, three regimes cover most of the listed universe:

The underlying definitions descend from the same CRIRSCO template, so resource and reserve categories translate directly. Procedure, filing triggers and the level of prescribed detail do not.

How Mining Terminal handles technical reports

Mining Terminal ingests technical reports from SEDAR+, ASX, EDGAR, LSE and other exchange feeds, and extracts the structured content — resource and reserve tables by category, cut-off grades, recovery assumptions, capital and operating costs, NPV and IRR by discount rate and price case, mine life, and Qualified Person attribution — with every value traced back to the document and page it came from.

Where a report discloses a figure without its scale or currency, we leave the field empty rather than infer it. A wrong number that looks precise is worse than no number.

To search technical-report economics across a commodity or jurisdiction, get in touch or ask Nara.

Sources

• National Instrument 43-101 Standards of Disclosure for Mineral Projects — Ontario Securities Commission
• NI 43-101 unofficial consolidation, effective 9 June 2023 — OSC PDF
• CIM Definition Standards for Mineral Resources and Mineral Reserves, 10 May 2014 — BCSC-hosted copy
• The JORC Code, 2012 Edition — jorc.org
• Regulation S-K subpart 1300 compliance guide — U.S. SEC

This article is educational and is not investment advice. Mining Terminal is a data platform, not a broker, dealer or investment adviser.