Mineral resources are naturally occurring substances that are solid, inorganic, and have a crystalline structure. They are found within a geologically defined envelope and can be divided into two major categories: metallic and non-metallic. Metallic resources include minerals such as gold, silver, copper, iron, and zinc, while non-metallic resources include things like sand, gravel, gypsum, and halite. Mineral resources are the key material basis for socio-economic development, providing raw materials for energy, industrial production, and agriculture.

A mineral resource is a concentration or occurrence of material of intrinsic economic interest in or on the Earths crust in such form, quality, and quantity that there are reasonable prospects for eventual economic extraction. Mineral resources are further sub-divided, in order of increasing geological confidence, into inferred, indicated, and measured categories. Inferred mineral resources are the part of a mineral resource for which quantity, grade, and mineral content can be estimated with a low level of confidence, while indicated resources are economic mineral occurrences that have been sampled to a point where an estimate has been made, at a reasonable level of confidence, of their contained metal, grade, tonnage, shape, densities, and physical characteristics.

Mineral reserves are the economically mineable part of a measured and/or indicated mineral resource, and they include diluting materials and allowances for losses that may occur when the material is mined or extracted. Mineral reserves are sub-divided in order of increasing confidence into probable and proved mineral reserves. The classification of mineral resources and reserves is important for the evaluation of mineral deposits worldwide and is based on the International Reporting Template developed by the Committee for Mineral Reserves International Reporting Standards (CRIRSCO) .