Mining reports: match resource claims to technical evidence
A mining presentation’s resource headline needs to match the technical report’s property, category, date and ownership basis. Finding a report with the same mine name is not enough. Build a claim-to-report card before interpreting a contained-metal number as reserves, recoverable production or current economic value.
Establish the regulatory object
The SEC’s mining disclosure compliance guide describes the S-K 1300 framework. Item 1302 addresses qualified-person support, technical report summaries and technical studies. This article concerns relevant US registrants; NI 43-101, JORC and other systems should be identified rather than treated as interchangeable labels.
Locate the actual report exhibit and record the property, estimate date, report signature date, filing date and responsible qualified person or permitted signing firm. Where several contributors are involved, inspect responsibility for the relevant sections. Employment or affiliation disclosures matter; do not assume that every report is signed by a fully independent individual merely because the description says qualified person.
Hypothetical headline reconciliation
Assume a fictional report identifies 10 million tonnes of a specified mineral-resource category at an average grade of 1.5 grams per tonne. The estimate covers the whole property, and the issuer has an 80% attributable interest. Assume the tonnage and grade belong to the same table and measurement basis.
Contained metal is 15 million grams, or 15 metric tonnes: 10 million times 1.5 grams. Applying the assumed 80% interest gives 12 metric tonnes attributable. A presentation headline of 12 tonnes can therefore agree with the gross report figure without any change in the underlying estimate.
| Hypothetical field | Technical report basis | Presentation check |
|---|---|---|
| Resource tonnage | 10 million tonnes | Same property and category? |
| Average grade | 1.5 grams per tonne | Same cut-off and estimate? |
| Gross contained metal | 15 metric tonnes | Not recoverable output |
| Attributable interest | 80% assumed | Ownership source required |
| Attributable contained metal | 12 metric tonnes | Matches only under stated basis |
Neither 15 nor 12 is automatically a mineral reserve or saleable metal. Recovery, dilution, modifying factors and the relevant study basis need their own evidence. Multiplying contained metal by a spot price would not turn the resource table into revenue or asset value.
Keep categories and dates intact
Record whether the claim concerns an exploration target, inferred resource, indicated resource, measured resource or reserve category. A target’s range is not a measured resource, and a resource cannot be relabeled a reserve because a presentation calls it high quality. Preserve category-specific uncertainty instead of combining all rows into one confident inventory number.
Suppose the estimate is dated December of Year 1, signed in March of Year 2 and reused in a Year 3 presentation. The newest presentation date does not make the technical estimate newly measured. Inspect subsequent filings for material changes and the basis for current reliance rather than declaring the report automatically valid or invalid from age alone.
Build the technical-evidence card
Use claim sentence, property identifier, category, tonnage, grade, units, cut-off, ownership, estimate date, signing responsibility, study type and report locator. Add assumptions about prices and relevant technical factors, keeping them separate from a live commodity quote. A later market move does not mechanically replace the report’s assumptions.
Review triggers include new drilling, changed ownership, materially revised cut-offs, altered development assumptions and a different reporting framework. A filing of a new exhibit may update only specified properties or sections; compare the actual scope rather than replacing every earlier research conclusion.
Public documents do not let an analyst recreate geological modeling or validate samples independently. The final note should state which headline is supported by which technical evidence, identify basis differences and preserve unresolved material changes. It verifies disclosure linkage, not a production forecast, an independent engineering certification or a reserve-replacement calculation.
FAQ
Does a qualified-person report guarantee the headline is a reserve?
No. Read the specific category, study basis and relevant conclusions.
Does a newly published slide refresh the technical estimate date?
No. Keep presentation, report-signing and underlying estimate dates separate.