AEM

Airborne electromagnetic survey

Ag

The chemical symbol for silver

Alluvial

Deposited by the action of running water in a stream

Alteration

Changes in the composition of a rock, generally chemical or mineralogical, brought about by weathering or hydrothermal activity

Arsenopyrite

A sulphide mineral of arsenic and iron (Fe AsS)

Assay

The chemical test of rock samples to determine their mineral content

Assay

To analyze the proportions of metals in an ore

Au

Chemical symbol for gold

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

Bench

The equivalent of a level in an underground mine most noticeable as the step-like features in an open-pit wall.  The open-pit bench height is calculated to match the rock strength, pit economics and capabilities of the open-pit machinery. Typical bench heights in open-pit mines range from 10 to 20 metres.

Best Cut

The optimum stoping width for mining of the reef at prevailing metal prices and costs.

BIC

Bushveld Igneous Complex

Birimian

Geological Time Era, about 2.1 billion years ago in which a suite of rocks characteristic to West Africa formed

Boudinage

A structure common in strongly deformed sedimentary and metamorphic rock, in which an original continuous competent layer or bed between less competent layers has been stretched, thinned and broken at regular intervals into bodies resembling boudius or sausages

Breccia/Brecciation

Rock type, formed from recrystallised fragments of other rocks

Capex

Capital expenditure

Carat

From the Arabic quirrat seed, unit for measuring the mass of precious stones; it is equal to 0,2g/0,00705 oz, and is part of the troy system of weights. It is also unit of purity in gold (US karat). Pure gold is 24-carat (the purest used in jewelry, is 22 parts gold and 2 parts alloy) to give greater strength.

Carbon-in-leach

A recovery process in which a slurry of gold ore, carbon granules and cyanide are mixed together. The cyanide dissolves the gold which is absorbed on the carbon. The carbon is subsequently separated from the slurry for further gold removal.

Carbon-In-Leach (CIL)

Similar to the CIP plant except the gold is leached and absorbed onto carbon granules in the same circuit. The carbon granules are separated and eluted in the same way as for CIP.

Carbon-in-pulp

Similar to carbon-in-leach process, but initially the slurry is subjected to cyanide leaching in separate tanks followed by carbon-in-pulp. Carbon-in-leach is a simultaneous process.

Carbon-In-Pulp (CIP)

Gold is leached conventionally from a slurry of gold ore with cyanide in agitated tanks. The leached slurry passed into the CIP circuit where carbon granules are mixed with the slurry and gold is absorbed onto the carbon. The granules are separated from the slurry and treated in an elution circuit to remove to gold

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.

Co

Chemical symbol for cobalt

Concentrating

This is the process of separating milled ore into a waste stream (tailings) and a valuable mineral stream (concentrate) by the flotation operation.  The valuable minerals in the concentrate contain almost all the base metal and precious metal minerals; these minerals are treated further by the smelting and refining process to obtain the pure metals (Cu, Ni and Platinum Group Metals).

Craton

A part of the earth's crust that has attained stability and has been little deformed for a long time

Cu

Chemical symbol for copper

Cut-off grade

The lowest grade material that can be included in a potentially economic intersection without dropping the overall grade below a specified level, referred to as the minimum mining grade. Lowest grade of mineralised material that qualifies as ore.

Decline

A generic term used to describe a shaft at an inclination below the horizontal and usually at the same angle as the dip of the reef

Development

The process of exposing an ore body through tunneling

Development

Any tunnelling operation which has for its object either exploration or exploitation.

Development waste

All development in country rock.

Development-Reef

All development on the reef horizon.

Diamond drilling

A rock drilling method using a rotary diamond bit which is attached to long hollow rods. The drill cuts a cylindrical core of solid rock, recovered for geological and metallurgical examination, and assay purposes

Dike

A tabular igneous intrusion that cuts across the planar structures of the surrounding rock

Dilution

Mixing of ore grade material with non-ore grade/waste material in the mining process

Dip

The angle that a structural surface, a bedding or fault plane, makes with the horizontal, measured perpendicular to the strike of the structure

Drill-core

The sample of rock obtained by diamond drilling

Dwt

Pennyweight

G/T

Grammes per metric tonne gold

Geophysical surveys

A survey method used primarily in the mining industry as an exploration tool, applying the methods of physics and engineering to the earth's surface. Exploration by observation of seismic of electrical phenomena and the earth's gravitational or magnetic fields, using specialized instrumentation

GIS

A geographical information system is a computerised relational database for spatial information

Grade

The amount of valuable element in each ton of ore, expressed as troy ounces per ton for precious metals and as a percentage for other metals

Cut-off grade is the minimum metal grade at which an ore body can be economically mined

Millhead grade is the metal content of mined ore going into a mill for processing

Recovered grade is actual metal content of ore determined after processing

Reserve grade is estimated metal content of an ore body, based on reserve calculations

Grade also "yield"

Gold recovered per unit of rock milled or treated. Normally measured as grams of gold per ton of rock

Grain

The smallest unit of mass in the three English systems (avoirdupois, troy and apothecaries' weights) used in the UK and USA, equal to 0,0648g. It was reputedly the weight of a grain of wheat. One pound avoirdupois equals 7 000 grains; one pound troy apothecaries weight equals 5 760 grains

Gram

Metric unit of mass; one thousandth of a kilogram

Granite

A medium to coarse grained igneous intrusive rock in which quartz constitutes 10 to 50 percent of the felsic components

Granitoid

Geological rock type

Hanging Wall

The overlying side of an orebody

Hard-rock gold mining

The mining of gold deposits in bedrock, i.e. deposits other than alluvial, colluvial or eluvial deposits

Head Grade

The gold contained in material passing through the mill in grams per tonne or troy ounces per short ton milled

Heap leaching

A process whereby metals are extracted by heaping broken ore on an impermeable pad, and repeatedly spraying with solutions which percolate through the heap, dissolving a high percentage of the metal content. The resulting mineral solution is then collected for metal recovery generally by electro-winning

Heap/dump leaching

A process whereby gold is extracted by "heaping" broken ore on sloping impermeable pads and repeatedly spraying the heaps with a weak cyanide solution which dissolves the gold content. The gold-laden solution is collected for gold recovery

Heavy minerals

Minerals with high specific gravity such as ilmenite, zircon, garnets, magnetite and rutile

Hedging

Generally refers to any precaution against risk. In the context of gold mines refer specifically to measures to reduce the risk of gold price fluctuations - particularly a fall in the gold price. Hedging has almost become standard practice to "insure" funding over the duration of large capital expenditure programs. Hedging the gold price is done by forward contracts and options and has developed into quite an art form.

Horizon

A plane of stratification assumed to have been once horizontal and continuous

Hydrothermal

Process of injection of heated or hot acqucous-rich solutions into existing rocks

Igneous

Formed by the solidification of hot mobile material termed magma

Indicated Mineral Resource

is that part of a Mineral Resource for which tonnage, densities, shape, physical characteristics, grade and mineral content can be estimated with a reasonable level of confidence.  It is based on exploration, sampling and testing information gathered through appropriate techniques from locations such as outcrops, trenches, pits, workings and drill holes.  The locations are too widely or inappropriately spaced to confirm geological and/or grade continuity but are spaced closely enough for continuity to be assumed

Inferred Mineral Resource

is that part of a Mineral Resource for which tonnage, grade and mineral content can be estimated with a low level of confidence.  It is inferred from geological evidence and assumed but not verified geological and/or grade continuity.  It is based on information gathered through appropriate techniques from locations such as outcrops, tenches, pits, workings and drill holes that may be limited or of uncertain quality and reliability

In-Situ

The original, natural state of the orebody before mining or processing of the ore takes place

Internal Waste

Any waste within the reef channel

Intrusion

The process of emplacement of magma (naturally occurring molten rock material generated within the earth) in pre-existing rock

IP Survey

Induced polarisation survey

Kimberlite fissures

Kimberlite fissures or dykes are intrusive bodies occurring along structural weaknesses in rocks. Generally economic diamond-bearing fissures in South Africa average 600mm to 800mm in width and may well be more than 5 km in strike length

Kriging

An interpolation method that minimises the estimation error in the determination of mineral resources

Leaching

The dissolving of elements and minerals out of ore

Lenticular

Resembling in shape the cross section of a lens

Long-hole stoping

A mining method involving drilling of long holes (up to 30 metres) into the orebody and then blasting a slice rock into an open chamber. The broken rock is then extracted leaving the chamber free for the next round of blasting

Lower Proterozoic

Era or geological time between 2.5 x 109 and 1.8 and 109 years before the present

MDM

Metallurgaical Design and Management

Measured Resource

That portion of a mineral resource for which tonnage, densities, shape, physical characteristics, grade and mineral content can be estimated with a high level of confidence.  It is based on detailed and reliable exploration, sampling and testing information gathered through workings and drill holes.  The locations are spaced closely enough to confirm geological and/or grade continuity

Merensky Reef

A band in the Bushveld sequence often containing economic grades of PGM.  Merensky Reef is the principal reef mined at Rustenburg Platinum Mines

Meta-morphosed

The mineralogical and structural adjustment of solid rocks to physical and chemical conditions which have been imposed at depth below the surface zones of weathering and cementation

Metallurgy

The science and art of separating metals from their ores by mechanical and chemical processes

Metasediment

A sedimentary rock that has undergone metamorphism

Metavolcanic

A rock which was volcanically extruded onto the surface and subsequently altered mineralogically by a combination of heat and pressure. (Metamorphism)

Meta-volcanics

Metamorphosed volcanic rocks

Mill

A plant where ore is ground fine and undergoes physical or chemical treatment to extract the valuable metals

Milling

Process to reduce broken ore to a size where concentrating can be undertaken

Mineral

A naturally formed chemical element of compound having a definite chemical composition and, usually, a characteristic crystal form

Mineral Reserve

is the economically mineable material derived from a measured and/or indicated Mineral Resource.  It is inclusive of diluting materials and allows for losses that may occur when the material is mined.  Appropriate assessments, which may include feasibility studies, have been carried out, including consideration of, and modification by, realistically assumed mining, metallurgical, economic, marketing, legal, environmental, social and governmental factors.  These assessments demonstrate at the time of reporting that extraction is justifiable.  Mineral Reserves are subdivided in order of increasing confidence into Probable Mineral Reserves and Proved Mineral Reserves

Mineral  Resource

is a concentration or occurrence of material of economic interest in or on the Earth's crust in such form and quantity that there are reasonable and realistic prospects for eventual economic extraction.  The location, quantity, grade, continuity and other geological characteristics of a Mineral Resource are known, estimated from specific geological evidence and knowledge, or interpreted from a well constrained and portrayed geological model.  Mineral resources are subdivided, in order of increasing confidence in respect of geoscientific evidence, into Inferred, Indicated and Measured categories

Mineral Resources

Any mineral deposit in such form and quantity that mining of the mineral may be feasible. The location, grade, quality and quantity of ore are estimated from specific geological evidence. Mineral resources are subdivided based upon the confidence of estimated qualities of that resource

Mineral sands

(heavy)

Alluvial sand deposits containing a varied combination of fine-grained heavy minerals

Mining Area

The area for which a mining authorisation /permision to mine has been granted

Mo

Chemical symbol for molybdenum

MOZ

Million troy ounces

MT

Million metric tons

Ni

Chemical symbol for nickel

On-reef development

Tunnels that are driven on the plane of The gold bearing reef. The most common form of on-reef development is "raise lines" that are driven up the dip of the reef

Open-pit

Open cut; mine worked at surface

Ore

Rock which contains a mineral or a concentration of minerals and/or metals which can be mined for a profit

Ore reserve

That part of a "Resource" which feasibility studies have shown "could be recovered economically under conditions realistically assumed at the time of reporting"

Orebody

Mostly solid and fairly continuous mass of mineralisation estimated to be economically mineable

Overburden

Uneconomic material which overlies a

bed of useful material; barren rock

material overlying a mineral deposit

Oxidised Ore

Ore that has decomposed by exposure to surface and near-surface elements

Oz

Ounce

Oz/ton

Ounce of a particular element per short ton of rock

Pay Limit

That grade at which the value of the ore is equal to the total cost of recovering the precious metal content

Pb

Chemical symbol for lead

PGM

Platinum Group Metals, six metallic elements found in association with each other and constitute the platinoids: Platinum (PI), Palladium (Pd), Rhodium (Rh), Ruthenium (Ru), Osmium (Os), and Iridium (Ir)

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

Placer

A surficial mineral deposit formed by mechanical concentration of mineral particles from weathered debris

Pluton

An igneous intrusion

Ppm

Parts of a particular element per million parts of rock or soil

Pre-feasibility study

The initial stage of the feasibility study in which the accuracy of the factors involved such as costs and revenues is +- 25%. Should the pre-feasibility study be positive, then the company would move to the final feasibility study

Probable Mineral Reserve 

is the economically mineable material derived from a Measured and/or Indicated Mineral Resource.  It is estimated with a lower level of confidence than a Proved Mineral Reserve.  It is inclusive of diluting materials and allows for losses that may occur when the material is mined.  Apppropriate assessments, which may include feasibility studies, have been carried out, including consideration of and modification by, realistically assumed mining, metallurgical, economic, marketing, legal environmental, social and governmental factors.  These assessments demonstrate at the time of reporting that extraction could reasonably be justified.

Probable Ore Reserve

The economically mineable part of an Indicated, and in some circumstances, Measured Mineral Resource, it includes diluting materials and allowances for losses which may occur when the material is mined.  Appropriate assessments, which may include feasibility studies, have been carried out and include consideration of and modification by realistically assumed, mining, metallurgica, economic, marketing, legal, environmental, social and governmental factors.  These assessments demonstrate at the time of reporting that extraction could reasonably be justified

Proved Mineral Reserve

is the economically mineable material derived from a Measured Mineral Resource.  It is estimated with a high level of confidence.  It is inclusive of diluting materials and allows for losses that may occur when the material is mined.  Appropriate assessments, which may include feasibility studies, have been carried out, including consideration of and modification by realistically assumed mining, metallurgical, economic, marketing, legal, environmental, social and governmental factors.  These assessments demonstrate at the time of reporting that extraction is reasonably justified. 

Proven Ore Reserve

The economically mineable part of a Measured Mineral Resource.  It includes diluting material and allowances for losses which may occur when the material is mined.  Appropriate assessments, which may include feasibility studies, have been carried out and include consideration of and modification by realistically assumed, mining, metallurgical, economic, marketing, legal, environmental, social and governmental factors.  These assessments demonstrate at the time of reporting that extraction could reasonably be justified

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

Quartz

Crystalline silica; silicon dioxide

Quartzite

A very hard, often metamorphosed, sandstone consisting chiefly of tightly cemented quartz grains

Quartzitic

Contining beds of quartzite, a sedimentary or metamorphic rock composed almost entirely of quartz grains

RC

Reverse circulation drilling

Reclamation

The process by which lands disturbed as a result of mining activity are reclaimed back to a beneficial land use. Reclamation activity includes the removal of buildings, equipment, machinery and 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

Recovery Rate

A term used in process metallurgy to indicate the proportion of valuable material obtained in the processing of an ore. It is generally stated as a percentage of the material recovered compared with the total material present

Reef

A gold-bearing quartz vein

Reef

Ore of economic interest

Refining

The final stage of metal production in which impurities are removed from the molten metal

Regolith

Fragmental and unconsolidated rock material overlying bedrock

Resource definitions

The mineral resources and mineral reserves of the Group are classified, verified and reported in accordance with statutory, stock exchange and industry/professional guidelines.  The classifications are based on the SAMREC Code.

Reverse circulation drilling (RC)

A drilling method using a tricone bit, during which rock cuttings are pushed to the surface through an outer tube by liquid and/or air pressure moving through an inner tube

Reverse fault

A thrust fault with a dip of 45" or less in which the hanging wall appears to have moved upward relative to the footwall

ROM

Run of Mine - equivalent to normal feed ore from mining operations

RP

Reconnaise permit

Sandstone

A medium-grained sedimentary rock composed of abundant fragments of sand size set in a fine-grained matrix of silt or clay

Saprolite

Weathered rock with distinguishable features/minerals of original rock

Schist

A strongly foliated crystalline rock formed by dynamic metamorphism

Sedimentary

Sourced from erosion of other rock

Shale

A fine-grained detrital sedimentary rock formed by the consolidation of clay, silt or mud and characterized by finely stratified structure

Shear zone

A tabular zone of rock that has been crushed and brecciated by many parallel fractures due to shear strain

Shrinkage mining:

A mining method often used when mining narrow orebodies, whereby a series of short holes are drilled into the face of the orebody. The rock is then blasted and remains until the entire zone is mined at which time the broken rock is extracted

Sintering

To form large particles, or lumps, or masses from, inter alia, metal powders by heating or pressure or both

Smelting

A metallurgical operation in which metal is separated from impurities by a process that includes fusion

Spot gold price

Refers to the open market gold price that we all hear on the radio or see in the morning paper. A spot price is the opposite of a contractual or fixed price, which remains constant over a certain agreed period

Sterilisation

Drilling carried out to ensure there is no hidden mineralisation below of permanent infrastrucutre (also known as condemnation drilling)

Stope

An area in an underground mine where ore is mined

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

Strike

The direction or trend that a structural surface, e.g. a bedding or fault plane, takes as it intersects the horizontal

Stringer

A mineral veinlet (typically less than 1cm wide), or filament occurring in a discontinuous pattern in the host rock

Stripping Ratio

The number of units of unpayable material which is to be mined in order to expose one unit of ore

Sulphide

A compound of sulphur with metallic element

Sweepings

The final process in stoping operations where the footwall is thoroughly cleaned to remove the last portion of broken ore and fines

Syncline

A concave upward fold, the core of which contains the stratigraphically younger rocks

T (t)

Tonne

Tailings

Finely ground rock material that remains once all economically-valuable metals are removed

Tailings

Ultra-fine particles of low residual value which are discarded by the metallurgical process

Tailings

The material that remains after all metals considered economic have been removed from ore during milling

Tailings Grade

The 4E content of the tailings produced by the milling and concentrating process - when compared to head grade is a measure of the efficiency of the concentrating process

Termitary

Geochemical sampling of residual surficial material (mounds) produced by termites

Ton

(Used in imperial statistics)

A short tone equal to 2 000 pounds

Tonne

(Used in metric statistics)

Equal to 1 000 kilograms

Tourmaline

A mineral commonly found as an accessory in intermediate to felsic igneous rocks, metamorphic rocks and certain sedimentary rocks

TPM

Metric tonnes per month

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 operation, e.g. from gullies and extraneous falls of ground, expressed in centimetres

Transport

The moving of broken rock to the shaft and the transport of men and materials to the working faces

Trend

The regional strike of a geological feature

Troy ounce

(Used in imperial statistics)

Equal to 31 10348 grams

Troy system

A system of units used for precious metals and gems. The pound troy (0.37kg) consists of 12 ounces (each of 120 carats) or 5 760 grains (each equal to 65 mg)

U

Chemical symbol for uranium

UG 2 Reef

A chromite layer within the critical zone of the Bushveld Igneous Complex

Unit working costs or gold production costs

Average working costs per unit of output, also referred to as gold production costs. In the case of gold mines this is usually expressed as rand per kilogram of gold. Other measures are rand per ounce and dollar per ounce

Unoxidised Ore

Ore that has not undergone changes/degradation due to the weathering process close to surface

Vein

A thin sheetlike crosscutting body of hydrothermal mineralization, principally quartz

Weathering

The destructive process constituting that part of erosion whereby earthy and rocky materials on exposure to atmospheric agents at or near the earth's surface are changed in character with little or no transport of the loosened or altered material

Whittle 4D

An optimisation computer program used for open pit mine design

Wireframe

Outline of an orebody based on varying parameters

Yield

The amount of valuable mineral in the ore expressed as grams per tonne or troy ounces per short ton

Zn

Chemical symbol for zinc