Mining Company research board

[1manband]

Industry Guide 7 is ancient. In practice, the SEC (and BLM) no longer permits companies to use the term "reserve" unless it is specifically in reference to proven reserves pursuant to a bankable (full) feasibility study. The SEC only permits the disclosure of proven and probable reserves. The same is true of all the industry standards organizations, including CIM, all of which only classify proven and probable as "reserves". Everything else is a now a "resource". If you want to use CIM's definitions, here they are. But note that the SEC does not permit US companies to disclose such resources or reserves in the same fashion as the Canadians do.

Inferred Mineral Resource (note nowhere does it refer to this as "reserves")
An ‘Inferred Mineral Resource’ is that part of a Mineral Resource for which quantity and grade or quality can be estimated on the basis of geological evidence and limited sampling and reasonably assumed, but not verified, geological and grade continuity. The estimate is based on limited information and sampling gathered through appropriate techniques from locations such as outcrops, trenches, pits, workings and drill holes.

Due to the uncertainty that may be attached to Inferred Mineral Resources, it cannot be assumed that all or any part of an Inferred Mineral Resource will be upgraded to an Indicated or Measured Mineral Resource as a result of continued exploration. Confidence in the estimate is insufficient to allow the meaningful application of technical and economic parameters or to enable an evaluation of economic viability worthy of public disclosure. Inferred Mineral Resources must be excluded from estimates forming the basis of feasibility or other economic studies.

Mineral Reserve
Mineral Reserves are sub-divided in order of increasing confidence into Probable Mineral Reserves and Proven Mineral Reserves. A Probable Mineral Reserve has a lower level of confidence than a Proven Mineral Reserve.

A Mineral Reserve is the economically mineable part of a Measured or Indicated Mineral Resource demonstrated by at least a Preliminary Feasibility Study.