This scheme defines concepts to specify the commodity property (eg copper, gold, dimension stone) in commodity descriptions associated with Earth Resource features. The commodity terms should be compatible with the endUsePotential categories associated with a MineralOccurrence (the concrete class that implements EarthResource). The ERML model states that the commodity term vocabulary should be hierarchical, to handle the group that the commodity belongs to (eg, base metal, precious metal, industrial mineral, energy). By extension, it includes all concepts in this conceptScheme, as well as concepts in any previous versions of the scheme.