Short answer
A mineral resource is an estimate of mineralisation in the ground that has reasonable prospects for eventual economic extraction. A mineral reserve is the economically mineable portion of a measured or indicated resource, demonstrated by a feasibility or pre-feasibility study that accounts for mining, processing, costs, and permitting. Reserves are a subset of resources — and the higher confidence number.
Why the distinction matters
A junior gold company can quote an enormous "resource" number that has never been tested against actual mining economics. A reserve number has been. Reserves require a study that proves the company can mine, process, and sell the gold at a profit at a stated long-term gold price.
Treat resource estimates as geological promise. Treat reserve estimates as a business case. They are not interchangeable.
The NI 43-101 categories
Canadian-listed mining issuers report under National Instrument 43-101. Resources are categorised by geological confidence: inferred (lowest), indicated, and measured (highest). Reserves are categorised by economic confidence: probable (derived from indicated resources) and proven (derived from measured resources).
Inferred resources cannot be converted directly to reserves. Only indicated and measured resources are eligible. The classification is signed off by a Qualified Person — a geoscientist or engineer who takes regulatory responsibility for the estimate.
How a resource becomes a reserve
Reserves are declared inside a study (pre-feasibility or feasibility) that defines a mine plan and proves economic viability at a long-term gold price assumption. The study tests pit shells, cut-off grades, recoveries, capital and operating costs, permitting risk, and reclamation.
Once the study is signed off, the indicated portion of the resource inside the mine plan becomes a probable reserve. The measured portion becomes a proven reserve.
Reading a resource statement
Look at three things: the gold price assumption (a generous price inflates the resource); the cut-off grade (a low cut-off pulls more rock into the resource); and the breakdown between measured, indicated, and inferred (a resource that is mostly inferred is a long way from being mineable).
Effective date matters too. A 43-101 resource is a point-in-time estimate; mining depletes it, and exploration replaces it. Compare the effective date of the resource against the company's latest production numbers.
Related questions
Can a gold company convert inferred resources directly to reserves?
No. Under NI 43-101, inferred resources are not classified with enough geological confidence to be converted directly to reserves. They must first be upgraded to indicated or measured through additional drilling.
What is a Qualified Person under NI 43-101?
A Qualified Person (QP) is a geoscientist or engineer with at least five years of relevant experience who takes professional responsibility for a 43-101 technical report. The QP must be a member in good standing of a recognised professional association.
Where can I find Majestic Gold's resource statement?
Majestic Gold Corp. files its technical reports on SEDAR+ at sedarplus.ca. The Songjiagou Gold Mine resource and reserve estimates are disclosed in the Company's NI 43-101 technical report filings.