Abstract
Demonstration of the feasibility of economic extraction is not required before Exploration
Results or Mineral Resources are reported. However, the use of Modifying Factors is
fundamental in demonstrating feasibility and thus in converting a Mineral Resource to a
Mineral Reserves. Understanding the application of theses Modifying Factors is
important to ensure the correct declaration of a Mineral Reserve. Failure to properly
investigate all relevant Modifying Factors can lead to the incorrect conversion of Mineral
Resources to Reserves, adding unnecessary risk to a project or even leading to premature
closure of a mine. The importance of correctly applying Modifying Factors to Mineral
Resources is discussed and examples provided to demonstrate the negative outcomes
when Modifying Factors are incorrectly applied.
Traditionally, mining engineers have looked to the more conventional Modifying Factors;
such as mining, metallurgical, legal, and economic factors. However, other factors, for
example, governmental, social and labour, environmental, and infrastructure factors,
previously thought by some engineers to be less significant, are now recognized as key
factors. The paper discusses the application of Modifying Factors and their importance in
establishing the feasibility of a mining project.