Cobalt Mining Legacy


This Glossary provides explanations of some of the terms used on this web site and in documents available for download from this site. It is based on the Glossary in AQUAMIN Supporting Document I, prepared as part of the Assessment of the Aquatic Effects of Mining in Canada. The author of this web site was also a principal author of that document. A number of definitions have been updated or added, using a number of sources, particularly the glossary of terms on the Northern Miner Online.



Acid: a substance containing hydrogen which, dissolved in water, tends to provide hydrogen ions (protons); or a substance having a tendancy to lose protons.

Acidic Drainage: acidic (and possibly metal containing) water resulting from the chemical weathering of rock or soil material primarily caused by the oxidation of sulphide minerals. Also referred to as Acid Mine Drainage (AMD) or Acid Rock Drainage (ARD)

Adit: an opening driven horizontally into the side of a mountain or hill for providing access to a mineral deposit.

Alkalinity: a measure of a water's capacity to neutralize an acid. It indicates the presence of carbonates, bicarbonates and hydroxides, and, less significantly, borates, silicates, phosphates and organic substances. It is expressed in milligrams of CaCO3 per litre.

Anthropogenic: created by humans.

Arsenide Mineral: a metallic mineral characterized by the covalent bonding of arsenic with a metal such as iron, nickel or cobalt. An example of an arsenide mineral is niccolite, which has the chemical formula NiAs.

Arsenides: see "Arsenide Minerals"

Arsenopyrite: an iron sulpharsenide mineral [FeAsS]. It is the most common arsenic mineral, and commonly occurs in association with gold.



Benthic: refers to organisms living at the bottoms of water bodies (marine or freshwater). Benthic organisms may live in or on the bottom sediment, or be attached to rocks.

Benthic Invertebrates: those animals without backbones living on and/or in the bottom of a water body.

Biomagnification: result of the processes of bioconcentration and bioaccumulation by which tissue concentrations of bioaccumulated chemicals increase as the chemical passes up through two or more trophic levels. The term implies an efficient transfer of chemical from food to consumer, so that residue concentrations increase systematically from one trophic level to the next.



Calcite: a calcium carbonate mineral [CaCO3]. A very common and widely distributed mineral.

Carbonate Minerals: a group of minerals whose fundamental unit is the carbonate anion (CO3)-2. The common cations in carbonates are Ca+2, Mg+2, Fe+2, Mn+2, Zn+2, Sr+2, Ba+2, Pb+2 and Cu+2.

Carbonates: see "Carbonate Minerals". Also, sedimentary or metamorphic rocks composed primarily of carbonate minerals.

Cobaltite: a cobalt sulpharsenide mineral [CoAsS].

Community: in ecology, a collection of populations of animals and plants that occur naturally together in a common environment, such as the organisms inhabiting a lake. The individuals and populations within the community interact with one another and with the abiotic (non-living) surroundings, with the community and abiotic surroundings together constituting an ecosystem. Communities vary considerably in size and one large community may contain a number of smaller ones.

Concentrate: the clean or final ore product recovered in concentration or separation stage of the milling process.

Conductivity: a numerical expression of the ability of an aqueous solution to carry an electric current. This ability depends on the concentrations of ion in solution, their valence and mobility, and on the solution's temperature. Conductivity in freshwater is normally reported in the SI unit of millisiemens per metre, or as micromhos per centimetre (1 mS/m = 10 µmhos/cm). Conductivity is a standard method for measuring salinity.

Contaminant: any physical, chemical or biological substance which is introduced into the environment. Does not imply and effect. Usually refers to substances of anthropogenic origin.

Cyanidation: a method of extracting exposed gold or silver grains from crushed or ground ore by dissolving it in a weak cyanide solution. May be carried out in tanks inside a mill or in heaps of ore out of doors.

Cyanide: a chemical inorganic salt of hydrocyanic acid (HCN) used in the milling process to dissolve precious metals such as gold and silver.



Deposit: mineral deposit or ore deposit is used to designate a natural occurrence of a useful mineral, or an ore, in sufficient extent and degree of concentration to invite exploitation.

Detection Limit: the smallest concentration or amount of a substance which can be reported as present with a specified degree of certainty by a definite, complete analytical procedure.

Dissolved Oxygen: the amount of oxygen present in solution in water, generally expressed in parts per million or mg/l.

Dolomite: a calcium magnesium carbonate mineral [CaMg(CO3)2].



Ecosystem: the organisms of a natural community together with their environment.

Effluent: a complex waste material which is a by-product of human activity (i.e., liquid industrial discharge or sewage) which may be discharged to the environment.

Eh: a Canadian idiom used at the end of any expression in order to turn that expression into a question. Also, a measure of the oxidation reduction potential.

Enargite: a copper sulpharsenide mineral [Cu3AsS4].

Erythrite: an hydrated cobalt arsenate mineral [Co3(AsO4)2·8H2O], formed through the oxidation of cobalt arsenide and sulpharsenide minerals.

Exploration: prospecting, sampling, mapping, diamond drilling and other work involved in searching for ore.



Flotation: a milling process in which valuable mineral particles are induced to become attached to bubbles and float as others sink.



Geochemistry: the study of the chemical properties of rocks.

Geology: the science concerned with the study of the rocks which compose the Earth.

Goethite: an iron oxyhydroxide mineral [FeO(OH)]. Forms through the oxidation of iron minerals.

Gypsum: an hydrated calcium sulphate mineral [CaSO4·2H2O].



Habitat: a geographic area that can provide for the key activities of life.

Hardness: the sum of calcium and magnesium concentrations, both expressed as CaCO3, in milligrams per litre. Other ions such as iron, manganese and aluminum contribute to total hardness, although they are usually present in much smaller concentrations and thus do not normally make a significant contribution to the total hardness. Waters of various hardness are classified as follows:

Hardness = 1 to 60 mg/l as CaCO3 soft water
Hardness = 61 to 120 mg/l as CaCO3 medium to hard water
Hardness = 121 to 180 mg/l as CaCO3 hard water
Hardness > 181 mg/l as CaCO3 very hard water

Headframe: the structure on top of a mine shaft which supports the hoist rope pulley, and often the hoist itself.

Heavy Metal: metallic elements with relatively high atomic weights (> 5.0 specific gravity) such as lead, cadmium, arsenic and mercury. Generally toxic in relatively low concentrations to plant and animal life.

Hydroxide Minerals: a group of minerals whose fundamental unit is the hydroxide anion, OH-. The common cations in hydroxides are Mg+2, Al+3, Fe+2, and Mn+2.

Hydroxides: see "Hydroxide Minerals."



Invertebrate: an animal without an internal skeletal structure. Invertebrates may have exoskeletons (e.g. lobster) or no skeletal structure (e.g. jellyfish).



Leaching: a chemical process for the extraction of valuable minerals from ore; also, a natural process by which ground waters dissolve minerals, thus leaving the rock with a smaller proportion of some of the minerals than it contained originally.



Mill: a plant in which ore is treated and metals are recovered or prepared for smelting; also a revolving drum used for the grinding of ores in preparation for treatment.

Milling: the part of the mining process by which minerals of economic value are recovered by: crushing and grinding; ore separation or concentration; and, dewatering of ore. The objective of milling is to separate minerals of economic value from the rock in which they occur.

Mineral: a naturally occurring homogeneous substance having definite physical properties and chemical composition and, if formed under favorable conditions, a definite crystal form.

Mining: excavation for the purpose of extracting valuable minerals from an economic ore deposit. Can be a surface or open mine or an underground mine.



Nugget: a small mass of precious metal, found free in nature.

Nutrient: a substance, element or compound necessary for the growth and development of plants and animals.



Ore: a natural minerals deposit in which at least one mineral occurs in sufficient concentrations to make mining the mineral economically feasible.

Oxidation: a chemical reaction in which electrons are lost from an atom and its charge becomes more positive. Normally, oxidation involves the addition of atmospheric oxygen or water. Oxidation occurs concurrently with reduction.

Oxide Minerals: a group of minerals whose fundamental unit is oxygen, O-2. The common cations in oxides include: Cu+2, Mg+2, Al+3, Fe+2, Mn+2, Ti+2, Cr+2 and Sn+2.

Oxides: see "Oxide Minerals".



Parts Per Billion (ppb): one unit of chemical (usually expressed as mass) per 1,000,000,000 units of the medium (e.g., water) or organism (e.g., tissue) in which it is contained. For water, the ratio commonly used is micrograms of chemical per litre of water, 1 µg/l = 1 ppb, for tissues, 1 µg/kg = 1 ng/g = 1 ppb.

Parts Per Million (ppm): one unit of chemical (usually expressed as mass) per 1,000,000 units of the medium (e.g., water) or organism (e.g., tissue) in which it is contained. For water, the ratio commonly used is milligrams of chemical per litre of water, 1 mg/l = 1 ppm, for tissues, 1 mg/kg = 1 µg/g = 1 ppm.

pH: a measure of the acidity or alkalinity of water, sediment or soil. The measure is based on the concentration of hydrogen ions, and gives the negative logarithm of the hydrogen (H+) ion, corresponding to 10-7. A pH value of 7 is neutral. All values higher are considered alkaline, and all values lower are considered acidic.

Population: a group of organisms of the same species living within a specified region. Populations have certain characteristics not shown by individual organisms or the community as a whole. Characteristics of a populations include density (size in relation to unit space), birth and death rates, age distribution, sex ratio, dispersion (distribution of individuals within the region) and growth rate.

Pyrite: a hard, heavy, shiny, yellow iron sulphide mineral [FeS2]. The most common and most widespread sulphide mineral. Occurs in a wide range of ore deposit types. Occasionally mined as a source of sulphur, but not as a source of iron. Also known as "fool's gold."



Quartz: a silicate mineral [SiO2]. One of the most common minerals in the world, occurring in a very wide range of rock types.



Reclamation: the process by which lands disturbed as a result of mining activity are reclaimed back to a beneficial land use. Reclamation activity may include the removal of buildings, equipment, machinery, other physical remnants of mining, closure of tailings impoundments, leach pads and other mine features, and contouring, covering and revegetation of waste rock piles and other disturbed areas.

Reduction: a chemical reaction in which electrons are gained by an atom and its charge becomes more negative. Reduction occurs concurrently with oxidation.



Safflorite: a cobalt iron nickel arsenide mineral [(Co,Fe,Ni)As2)].

Scorodite: an hydrated iron arsenate mineral [FeAsO4·2H2O], formed through the oxidation of iron arsenide and sulpharsenide minerals.

Sediment: solid fragmental material that originates from weathering or rocks and is transported or deposited by air, water or ice, or that accumulated by other processes, such as chemical precipitation from solution or secretion by organisms. The term is usually applied to material held in suspension in water or recently deposited from suspension and to all kinds of deposits, essentially of unconsolidated materials.

Shaft: a vertical or inclined excavation in rock for the purpose of providing access to an orebody. Usually equipped with a hoist at the top, which lowers and raises a conveyance for handling workers and materials.

Silicate Mineral: a large group of minerals whose fundamental unit is SiO4. A wide range of metals can occur in silicates, including Fe, Mg, K, Al, and Ca. Silicates comprise about one third of all mineral species, and are important rock forming minerals, comprising up to 95% of the earth's crust.

Silicates: see "Silicate Mineral".

Skutterudite: a cobalt nickel arsenide mineral [(Co,Ni)As2-3].

Slurry: a fluid mixture of liquids and solids.

Species: a group of plants, animals or microorganisms that have a high degree of similarity and generally can generally interbreed only among themselves.

Sulpharsenide Mineral: a metallic mineral characterized by the covalent bonding of sulphur and arsenic with a metal such as iron, copper, lead, zinc, nickel or molybdenum. An example of a common sulpharsenide mineral is arsenopyrite, which has the chemical formula FeAsS.

Sulpharsenides: see "Sulpharsenide Mineral"

Sulphate Mineral: a mineral characterized by the bonding of sulphate anion with a metal such as barium, calcium, lead or copper. Sulphates may or may not include water in their structure. Common examples include barite [BaSO4] and gypsum [CaSO4·2H2O].

Sulphate: an anion with the formula SO4-2.

Sulphates: see "Sulphate Mineral"

Sulphide Mineral: a metallic mineral characterized by the covalent bonding of sulphur with a metal or semimetal, such as iron, copper, lead, zinc, nickel or molybdenum. An example of a common sulphide mineral is pyrite, which has the chemical formula FeS2. Sulphide minerals occur in a wide range of geological environments. When occurring in sufficient concentrations, sulphide minerals can be important ore minerals for a range of base metals, including copper, lead, zinc and nickel.

Sulphides: see "Sulphide Mineral"

Sulphosalt Mineral: a type of sulphide mineral in which both a metal and a semimetal occur. For example, enargite, Cu3AsS4, would be considered a sulphosalt since it contains both arsenic and sulphur. Such minerals may also be considered sulpharsenides.

Sulphosalts: see "Sulphosalt Mineral"

Suspended Solids: and solid substance present in water in an undissolved state, usually contributing directly to turbidity.



Tailings: the waste material and water mixture that is leftover after the mill removes the valuable rocks. The rock material in tailings is usually the size of sand grains or smaller.

Tailings pond: a low-lying depression used to confine tailings.

Toxicity: the inherent potential or capacity of a material to act on a group of selected organisms, under defined conditions. An aquatic toxicity test usually measures the proportion of organisms affected by their exposure to specific concentrations of chemical, effluent, elutriate, leachate, or receiving water.

Toxicity Test: the means by which the toxicity of a chemical or other test material is determined. A toxicity test is used to measure the degree of response produced by exposure to a specific level of stimulus (or concentration of chemical).

Trench: a long, narrow excavation dug through overburden, or blasted out of rock, to expose a vein or ore structure.



Vein: a fissure, fault or crack in a rock filled by minerals that have travelled upwards from some deep source.



Waste Rock: rock which does not contain any minerals in sufficient concentration to be considered ore, but which must be removed in the mining process to provide access to the ore.

Wetlands: habitats where the influence of surface or ground water has resulted in the development of plant or animal communities adapted to such aquatic or intermittently wet conditions. Wetlands include tidal flats, shallow subtidal areas, swamps, marshes, wet meadows, bogs, muskeg, and similar areas.