Backfill
Waste material used to fill the void created by mining an ore
body with the purpose of providing both regional and localised support. Below collar
A distance below the surface elevation of a shaft.
Carbon-in-pulp (CIP)
Gold is leached conventionally from a slurry of gold ore with
cyanide in agitated tanks. The leached slurry passes into the CIP circuit where carbon
granules are mixed with the slurry and gold is adsorbed onto the carbon. The granules are
separated from the slurry and treated in an elution circuit to remove the gold.
Carbon-in-leach (CIL)
Similar to a CIP plant except the gold is leached and adsorbed
onto carbon granules in the same circuit. The carbon granules are separated and eluted in
the same way as for CIP.
Cash costs
Cash costs include site costs for all mining (excluding
deferred development costs), processing and administration, but are exclusive of
royalties, production taxes, amortisation and rehabilitation, as well as corporate
administration, capital and exploration costs.
Channel width
The total thickness of all reef bands including internal
waste.
Development
The process of exposing an ore body through tunnelling.
Development-reef
All development on the reef horizon.
Development-waste
All development in country rock.
Head grade
The gold contained in material passing through the mill in
grams per tonne or troy ounces per short ton milled.
Internal waste
Any waste within the reef channel.
Pay limit
That grade at which the value of the ore is equal to the total
cost of recovering the precious metal content.
Pillar mining
The mining of scattered blocks of reef of variable size
usually associated with older shafts, which have been left behind and are now being mined
in the final clean-up stage of the mine's ore body.
Productivity
An expression of labour productivity based either upon the
ratio of grams of gold produced to the total number of employees or the area mined in
square metres to the total number of employees.
Reef
Ore of economic interest.
Stopes
Underground excavations where the ore body is extracted on the
plane of the reef.
Stoping
The process of mining the ore body on the plane of the reef.
Stoping width
The sum of the channel width and external waste widths.
Tailings
Ultra-fine particles of low residual value which are discarded
by the metallurgical process.
Tonne
(Used in metric statistics)
Equal to 1 000 kilograms.
Ton
(Used in imperial statistics)
A short ton equal to 2 000 pounds.
Tramming width
A dimension used to denote the effect of waste tons in the
stoping operation, such as from gullies, on the reef tons produced. It is the sum of the
channel width plus the impact of waste tonnage in the stoping operations, e.g. from
gullies and extraneous falls of ground, expressed in centimetres.
Troy ounce
(Used in imperial statistics)
Equal to 31,10348 grams.
Yield
The amount of valuable mineral in the ore expressed as grams
per tonne or troy ounces per short ton. |