Glossary

Glossary

B

Below Collar

A distance below the surface elevation of a drill hole collar or shaft

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 boudins or sausages

Breccia/Brecciation

Rock type, formed from recrystallised fragments of other rocks

C

Capex

Capital expenditure

Co

The 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 (Ag, Au, Cu, Ni, Pb, Zn, 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

The 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.

D

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

Dyke

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

F

Fault

A fracture in rock along which there has been an observable amount of displacement

Feasibility study

A definitive engineering study addressing the economic viability of bringing a deposit to the production stage; taking into consideration all associated costs, revenues and risks. The study is used to support the search for project financing.

Footwall

The underlying side of an orebody

G

g/t

Grams per metric tonne

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 per tonne of rock (g/t) for precious metals and in percent (%) for base metals

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

An igneous rock type

H

Hanging Wall

The overlying side of an orebody

Head Grade

The gold contained in material passing through the mill in grams per tonne or troy ounces per short ton milled for precious metals and percent concentration of metal for base metals

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.

Hydrothermal

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

I

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, trenches, 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

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

K

K

Chemical symbol for potassium

Kriging

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

L

Lenticular

Resembling in shape the cross section of a lens

Lower Proterozoic

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

M

m

Metre

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

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

Mining Area

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

Moz

Million troy ounces

Mt

Million metric tons

N

Ni

The chemical symbol for nickel

O

Open-pit

Open cut; mine worked at surface

Ordovician Period

Ordovician Period is the second period in the Paleozoic Era that occurred between 485.4 million and 443.8 million years ago before present.

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

oz

Ounce

Oz/ton

Ounce of a particular element per short ton of rock

P

Pb

The chemical symbol for lead

PGM

Platinum group metals usually including platinum, palladium and other minor metals.

Pluton

An igneous intrusion

Polymetallic (massive sulphide) Deposits

Polymetallic massive sulphide deposits are most commonly formed along tectonic plate boundaries and volcanic provinces in water depths from <500 to 5,000m. Seawater seeps into the volcanic rock making up the seafloor through cracks and fissures. As this fluid becomes heated it circulates through the sub-seafloor, dissolving metals and other elements from the surrounding rocks. Convection carries this hot (up to 450°C), acidic, metal-rich fluid back up towards the surface where it is expelled at the seafloor, creating hydrothermal vents. As this hot fluid reacts with the cold seawater particles of metal sulphide minerals precipitate from the fluid and settle out on the seafloor, creating a layer rich in copper, lead, zinc, precious and trace metals. Also often referred to as a VMS (volcanic massive sulphide) deposit

ppb

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

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

This 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. 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 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, metallurgical, 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

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

Q

Quartz

Crystalline silica; silicon dioxide

Quartzite

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

R

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

Refining

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

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 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

S

Sandstone

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

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

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

Sterilization

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

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

Syncline

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

T

T (t)

Metric tonne (2,200 lbs) or short ton or imperial ton (2,000 lbs)

Tailings

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

Tailings Grade

The metal content of the tailings produced by the milling and concentrating process—when compared to head grade is a measure of the efficiency of the extraction process

Termitary

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

Ton (used in imperial statistics)

A short ton is 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

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

U

Chemical symbol for uranium

Underground Mine

Under ground workings; mine worked below surface with access via by a ramp, adit or shaft

V

Volcanic belt

A sequence of rocks formed in the earth’s crust through a volcanic event

VMS Deposit

Volcanic massive sulphide deposit. A type of ore deposit formed during a volcanic event usually in a sea floor environment. See also Polymetallic Deposit above.

Vein

A thin sheet-like crosscutting body of hydrothermal mineralization, principally quartz

W

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

Wireframe

Outline of an orebody based on varying parameters

Z

Zn

The chemical symbol for Zinc