We have put together a list of definitions for therms related with the mining activities to make it easier for you to understand the content of this website.
ACID MINE DRAINAGE
Acid Rock Drainage (ARD) is a natural process whereby sulphuric acid is produced when sulphides in
rocks are exposed to air and water. Acid Mine Drainage (AMD) is essentially the same process, greatly
HEAVY METAL CONTAMINATION & LEACHING
Heavy metal contamination and leaching occurs when the metals contained in excavated rock or
exposed in an underground mine come in contact with water. Metals are leached out and carried
downstream as water washes over the rock surface. Although metals can become mobile in neutral pH
conditions, leaching is particularly accelerated in the low pH conditions such as are created by acid mine
An ore is a type of rock that contains minerals with important elements including metals. The ores are
extracted through mining and then refined to extract the valuable element(s).
Overburden (also called waste or spoil) is the material that lies above an area with economic or scientific
interest. In mining, it is most commonly the rock, soil, and ecosystem that lies above a coal seam or ore
body. Overburden is removed during surface mining.
Smelting is a form of extractive metallurgy; its main use is to produce a metal from its ore. This includes
production of silver, iron, copper and other base metals from their ores. Smelting uses heat and a
chemical reducing agent to decompose the ore.
Tailings, also called mine dumps, culm dumps, slimes, tails, refuse, leach residue or slickens,are the
materials left over after the process of separating the valuable fraction from the uneconomic fraction
(gangue) of an ore. Tailings are distinct from overburden.