Mineral Resource Classification is the systematic categorization of mineralization within a deposit according to the level of geological confidence and data density supporting it. Under CRIRSCO-aligned reporting codes, resources are classified into three categories: Measured Resources, which have the highest confidence based on closely spaced, high-quality sampling and demonstrated geological and grade continuity; Indicated Resources, which have a reasonable level of confidence sufficient to support mine planning; and Inferred Resources, which are based on limited data and lower confidence, and therefore cannot be converted directly into Mineral Reserves. Classification criteria typically consider drill hole spacing, sample quality, geological interpretation reliability, and grade continuity modelling. The classification approach varies across commodities; for example, gold deposits with high nugget effects or narrow vein structures may require tighter drill spacing to achieve Measured status, iron ore deposits hosted in laterally continuous banded iron formations can often be classified with wider spacing, bauxite laterite deposits rely heavily on shallow auger drilling grids, and diamond deposits, particularly alluvial and kimberlite occurrences, often require large-diameter bulk sampling due to the highly erratic, low-frequency distribution of diamonds within the host material.
