Decreasing Metal Ore Grades—Is the Fear of Resource Depletion Justified?

Abstract

Metals are an essential part of modern living. Ensuring the future supply of metals is a key issue in politics, science, and economics because the available amount of mineral resources is limited. To measure the depletion of mineral resources, several indicators are used. Some of them are based on the ore grade, which has been decreasing over time and is thus taken as a sign of resource exhaustion. However, does this assumption hold true? This paper shows that the development of ore grades is mainly the result of the increasing demand and the outstanding technological improvements that made mining of low grade ores profitable. The usage of ore grades as an indicator may, therefore, lead to erroneous conclusions about the safeguard objects. These are not the metals themselves, but the environment that is impacted by their extraction.

Keywords

• resource depletion
• ore grade
• metals
• copper
• influencing factors
• indicators