GLOSSARY



 

Active workings Any place in a mine where miners are normally required to work or travel and which are ventilated and inspected regularly.
Adit Entrance to a mine, generally a horizontal tunnel.
Airborne survey Exploration work conducted from an aircraft. Includes aerial photographic surveys and geophysical surveys to measure magnetism or radioactivity.
Alteration Change in a rock's mineralogic composition caused by heat, pressure, mechanical weathering by wind or water, or exposure to chemicals in hydrothermal solutions. Milder and more localized than metamorphism. Certain types of alteration can be indicative of nearby ore mineralization; for example, chlorite and sericite alteration often surround porphyry copper and gold deposits.
Anomaly An observed or measured deviation from normal geologic conditions generally used to describe features that may suggest an ore deposit. Geochemical anomalies such as high arsenic content, or geophysical anomalies such as high magnetism, may signal the presence of mineralization.
Assay A measure of the amount of an economic metal within an ore sample. The act of collecting such a measure.
Assay map Schematic of an exploration property showing sampling locations and assay grades.