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Glossary

“A” Grade Coal

Domestic South African bituminous coal with a Air Dried basis CV between 27.5 – 28.5 Mj/kg.

Abrasion Index

Abrasion is the property of the coal which describes its propensity and ability to wear away machinery and undergo autonomous grinding. While carbonaceous matter in coal is relatively soft, quartz and other mineral constituents in coal are abrasive. This is tested in a calibrated mill, containing four blades of known mass. The coal is agitated in the mill for a defined period at a defined rate. The abrasion index is determined by measuring the loss of mass of the four metal blades.

Accepted

An application for an exploration right which has been accepted in terms of Section 16(2) of the MPRDA.

Air Dried or AD

Coal mass that includes inherent moisture (IM).

Algorithm

Mathematical functions used in geological highwall software to determine various geological information and coal resource estimates.

Analyses

Process of determining the physical and chemical properties of a coal sample.

Ash Content or Ash

The solid residue that remains after the complete combustion of coal. Is a measure of the non-combustible material in coal expressed as a percentage.

As Received or AR

Coal mass that includes total moisture (TM).

“B” Grade Coal

Domestic South African bituminous coal with a Air Dried basis CV between 26.5 – 27.5 Mj/kg.

Band

A coal seam can be divided vertically into different regions based on coal quality or other characteristics; a band refers to one of these regions. Alternatively referred toas a ply.

BEE

Broad-based black economic empowerment as defined in the MPRDA.

Bench

A ledge that, in open-pit mine and quarries, forms a single level of operation above which minerals or waste materials are excavated from a contiguous bank or bench face. The mineral or waste is removed in successive layers, each of which is a bench, several of which may be in operation simultaneously in different parts of, and at different elevations in, an open-pit mine or quarry.

Bituminous Coal

A medium quality coal mostly used in for raising steam for the generation of electricity.

Bord

Opening formed by mining using the bord and pillar method of mining.

Bords

Are areas from which the coal has been mined; pillars are the areas of coal left between the bords.

Borehole Log

A graphical representation of the information revealed by vertical diamond drilling.

Boxcut

The initial cut driven in a property, where no open side exists; this results in a highwall on both sides of the cut.

btu/lb

British Thermal Units per pound. An alternative measure of CV, used outside South Africa. To convert btu/lb to MJ/kg divide btu/lb by 430.

“C” Grade Coal

Domestic South African bituminous coal with a Air Dried basis CV between 25.5 – 26.5 Mj/kg.

Calorific Value or CV

The heating value of coal. To determine the calorific value (CV), a known mass of air-dried coal is burned under standard conditions in an oxygen atmosphere contained in a constant volume. The gross CV is the standard South African method for reporting CVs and is measured in MJ/kg– it can also be measured GJ/t (Gigajoules/tonne), kcal/kg or btu/lb.

Gross CV, or “upper heating value” is the CV under laboratory conditions. Net CV, or “lower heating value” or “Net Effective Calories” (NEC) is the useful calorific value in the boiler plant. The difference is essentially the latent heat in the water vapour produced.

Cash Cost

Direct mining costs, direct processing costs, direct general and administration costs, consulting fees, management fees, transportation, treatment charges and profit sharing charges.

cm

Centimetre or centimetres, as the context indicates.

Coal

A black or brownish black solid, combustible substance formed by the partial decomposition of vegetable matter without access to air. The rank of coal, which may take the form of anthracite, bitumous coal, sub-bitumous coal and lignite, is based on its fixed carbon, volatile matter and heating values (CV). Coal rank indicates the progressive alteration, or coalification, from lignite to anthracite.

Coal Reserve

The economically mineable material derived from a measured and/or indicated coal 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 reasonably justifiable. Coal reserves are subdivided in order of increasing confidence into probable coal reserves and proved coal reserves.

Coal Resource

A concentration or occurrence of coal in or on the earth’s crust in such form and quantity that there are reasonable and realistic prospects for eventual economic extraction.

Cobbles

Coal of square mesh screen size greater than 31.5 mm and less than 100 mm.

Colliery

A coal mine together with its physical plant and buildings. In South Africa the term “Colliery” applies to both underground and open-pit coal mines.

Competent Person

A person that is registered with any one of: the South African Council for Natural Scientific Professionals, the Engineering Council of South Africa, the South African Council for Professional Land Surveyors and Technical Surveyors; or any other statutory South African or international body that is recognized by SAMREC.

Cone Crusher

A crushing device in which material is comminuted between an eccentrically moving cone and an outer conical shell.

Contamination

The inclusion of waste rock in the coal seam mined as a result of mining operations.

Conveyer or Conveyer Belt

A mechanical apparatus consisting of a continuous moving belt that transports coal from one place to another.

CPR

Competent Persons’ Report.

csv

Comma Separated Values, the most common import and export format for spreadsheets and databases.

Cut-Offs

The lowest grade of mineralised material that qualifies as Mineral Resources in a given deposit.

Cyclone

Equipment used in the washing of coal; used to separate waste from a coarse coal/waste mixture.

“D” Grade Coal

Domestic South African bituminous coal with a Air Dried basis CV less than 25.5 Mj/kg.

DEAT

The South African Department of Environment and Tourism.

Devolatilised Coal

Generally South African bituminous coal which contains less than 20% volatile matter.

Diagenesis

The process of chemical and physical change in deposited sediment during its conversion to rock.

Diamond Drilling

The act or process of drilling boreholes using bits inset with diamonds as the rock-cutting tool. The bits are rotated by various types and sizes of mechanisms motivated by steam, internal-combustion, hydraulic, compressed air, or electric engines or motors. A common method of prospecting for coal deposits.

Dilution

The inclusion of a non select ply of coal with the ply of coal being selectively mined. This can affect profitability or coal processing performance.

Dip

Inclination of geological features from the horizontal.

Discard

Waste material (generally solid) produced as a generally unwanted by-product from the beneficiation of the coal.

DM

Dense Medium.

DME

The South African Department of Minerals and Energy.

DMS

Dense Medium Separation.

Dolerite

Any dark, igneous rock composed chiefly of silicates of iron and magnesium with some feldspar.

Dome

An uplift or anti-clinal structure, either circular or elliptical in outline, in which the rocks dip gently away in all directions.

Dry-Ash-Free Volatiles or DAF Vols

The volatiles expressed as percentage without the other proximate analyses (Ash and moisture).

Dry Basis (DB)

Coal mass that excludes total moisture.

DTM

Digital Terrain Model.

Duff

Coal of square mesh screen size less than 6.3 mm.

DWAF

The South African Department of Water Affairs and Forestry.

Dyke

A tabular igneous intrusion that cuts across the bedding or foliation of the country rock.

Ecca Group

Stratigraphic sequence in Southern Africa containing coal deposits.

EIA

Environmental Impact Assessment.

EMP

Environmental Management Plan.

EMPR

Environmental Management Programme Report.

Erosional Surface

Ground surface or lithological unit that has been subjected to weathering or geological erosion.

Exploration

The intentional searching for coal, but not including mining.

Exploration Results

The results of exploration which are compiled by a competent person.

Export quality coal

In the South African context “export quality coal” generally refers to coal that meets the RB1 and RB2 specification or alternatively is an “A” or “B” grade coal. Anthracite and metallurgical coal is also exported from South Africa.

Fault

Fracture or a fracture zone in crustal rocks along which there has been displacement of the two sides relative to one another parallel to the fracture.

Fines

Dewatered coal of square mesh screen size less than 1 mm.

Fixed Carbon or FC

The organic residue remaining after the volatile matter has been liberated. The percentage of fixed carbon is obtained when the sum of the moisture, ash and volatile matter percentages is subtracted from a 100.

Floats

Material during the testing or washing process that floats on the testing or washing medium; generally forming the product coal fraction.

Flocculant

Reagent used to assist in froth flotation process of coal processing, or in the settling of solids to enable process water to be re-used in the processing of the coal.

Footwall

The part of the country rock that lies below the deposit.

g

grams

Gangue

Worthless rock or other material found within the coal.

GIS

Geographical Information System.

Grains

Coal of square mesh screen size greater than 3.1 mm and less than 12.5 mm.

Granted

A right to prospect which is granted in terms of Section 17(1) of the MPRDA.

GTIS

Gross tonnage in situ with no modifying factors.

Ha, ha or Hectare

A measurement of area 100 metres by 100 metres.

Hangingwall

The overlying side of an orebody or bord.

Hardgrove Grindability Index

Is a measurement of coal grindability...in a laboratory mill of standard design. The percent by weight of the coal that passes through a screen with openings of 74 micrometres is used to calculate the Hardgrove grindability index (HGI). The index is used as a guideline for sizing the grinding equipment in a coal-preparation plant.

Haul Road

A road built to carry heavily loaded trucks at a good speed in an open pit. The grade is limited on this type of road and usually kept to less than 17% of climb in direction of load movement.

Haulage

An underground drive used for mechanical transport.

HDP

A historically disadvantaged person as defined in the MPRDA, being:

- any person, category of persons or community, disadvantaged by unfair discrimination before the Constitution of the Republic of South Africa No. 108 of 1996 took effect;

- any association, a majority of whose members are persons contemplated in the first bullet above; or

- any juristic person other than an association, in which persons contemplated in the first bullet above own and control a majority of the issued capital or members’ interest and are able to control a majority of the members’ votes.

HEPS

Headline earnings (or loss) per share.

Highwall

Edge of open-pit operations in advance of the direction of mining.

HQ

Diamond drill core size 63.5mm in diameter.

IFRS

International Financial Reporting Standards.

Igneous

Said of a rock or mineral that solidified from molten or partly molten material, i.e., from a magma; also, applied to processes leading to, related to, or resulting from the formation of such rocks. Igneous rocks constitute one of the three main classes into which rocks are divided, the others being metamorphic and sedimentary.

In Situ

Generally used with reference to the reporting of coal resources to indicate a volume or tonnage of coal present undisturbed in the ground.

In Situ Tonnage

Measure of mass of coal in the ground (each tonnage quoted needs to be specified whether it is air dried or moisture free).

Indicated Coal Resource

That part of a coal resource for which tonnage, densities, shape, physical characteristics, grade and coal 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 for continuity to be assumed.

Inherent Moisture

Moisture held within the coal itself.

Inferred Coal Resource

That part of a coal resource for which tonnage, grade and coal content can be estimated with a low level of confidence. It is inferred from geological evidence and assumed but not verified for 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.

Intercalated

Intercalated material is layered material that exists or is introduced between layers of a different character; especially a relatively thin strata of one kind of material that alternates with thicker strata of some other kind, such as beds of shale intercalated in a body of sandstone.

Interested and Affected Parties

A term used in the context of an environmental study to refer to those people or parties who will be affected by or have an interest in the outcome of the environmental study. Interested and affected parties can include farmers, land dwellers, neighbours, conservation organizations, municipalities, other government departments etc.

Intrusion

In geology, a mass of igneous rock that, while molten, was forced into or between other rocks.

ISO

International Standards Organisation.

Jaw Crusher

A machine for reducing the size of materials by impact or crushing between a fixed plate and an oscillating plate, or between two oscillating plates, forming a tapered jaw.

JSE

JSE Limited (Registration number 2005/022939/06), a public company registered and incorporated in South Africa, licensed as an exchange under the South African Securities Services Act, No 36 of 2004, as amended.

Karoo Supergroup

Stratigraphic sequence in Southern Africa containing coal deposits.

kcal/kg

Kilocalories per kilogram. An alternative measure of CV, used outside South Africa. To convert kcal/kg to MJ/kg divide kcal/kg by 238.8.

km

kilometer or kilometers, as the context indicates.

Large Cobbles

Coal of square mesh screen size greater than 31.5 mm and less than 150 mm.

Large Nuts

Coal of square mesh screen size greater than 31.5 mm and less than 70 mm.

Lean Coal

Generally South African bituminous coal which contains less than 15% volatile matter.

Long Life

Operation with life of greater than 10 years.

Low Wall

Edge of open-pit operations behind the general direction of mining.

LT

Imperial or Long ton = 1 016.05 kilograms = 2 240 lb. This measure of mass is not used in South Africa.

Lumps

Coal of square mesh screen size greater than 100 mm.

m or metre

metre or metres, as the context indicates.

Maceral Composition

Of a coal and is determined by the nature of the original plant material and its degree of alteration during the process of diagenesis.

Magnetite Medium

Addition to the washing fluid (generally water) of fine magnetite particles to increase the relative density, generally in a DMS, allowing the coal to be separated from a coal/waste mixture.

mamsl

Meters above mean sea level .

Measured Coal Resource

That part of a coal resource for which tonnage, densities, shape, physical characteristics, grade and coal content can be estimated with a high level of confidence. It is based on detailed and reliable exploration, sampling and testing information gathered through appropriate techniques from locations such as outcrops, trenches, pits, workings and drill holes. The locations are spaced closely enough to confirm geological and grade continuity.

Medium-Life

Operation with life of between 5 and 10 years.

Megawatt

1 million watts.

Minimum Mining Width

The minimum mining width at which an in-situ Coal Resources is stated.

MJ/Kg

megajoules per kilogram, measure of heat generating capacity (cv).

mm

millimetre or millimetres, as the context indicates.

Moisture Content

May include reference to the free or surface moisture, inherent moisture or the bed moisture of a coal. Surface moisture is that water present on the external surface of the coal, and inherent moisture occurs in the pores of the coal. Surface moisture is removed by air drying. The moisture content of a coal as given in a proximate analysis is derived from the mass loss of air-dried coal (i.e. free of surface moisture) when heated to between 105 and 110 degrees Celsius.

Moisture Free

Coal mass that has been adjusted to exclude moisture.

MPRDA or Mineral and Petroleum Resources Development Act or MPRDA

the South African Mineral and Petroleum Resources Development Act No. 28 of 2002, as amended, which became effective legislation on 1 May 2004.

MT, t

Metric Tonnes where 1 MT = 1 000 kilograms = 2 204.6 lb. MT are the standard measure of mass in South Africa.

Mt

Million Tonnes.

MTIS

Mineable Tonnes in situ.

MW

Mega Watt.

Nuts

Coal of square mesh screen size greater than 20 mm and less than 40 mm.

Open Pit

A mine working or excavation, open to the surface.

Overburden

Designates material of any nature, consolidated or unconsolidated, that overlies an economic deposit.

Peas

Coal of square mesh screen size greater than 6.3 mm and less than 25 mm.

Perennial

Describing a watercourse that flows throughout the year.

Phreatic Surface

Level of water generally in a waste or discard facility constructed on the topographical surface.

Piezometer

Instrument used to determine the level of water in a borehole or to determine a phreatic surface in a waste or discard disposal facility.

Pillar

A block of coal, left intentionally for purposes for ground control or on account of low value.

Ply

A coal seam can be divided vertically into different regions based on coal quality or other characteristics; a ply refers to one of these regions. Alternatively referred to a Band.

Proterozoic

A geological era.

Proximate Analysis

Analysis carried out on coal to determine commonly reported qualities – ash content, volatiles, fixed carbon, sulphur and calorific value can be expressed on a As Received (AR), Air Dried (AD), Dry (DB) or Dry Ash Free (DAF) basis.

Pseudo Anthracite

Coal that has been devolatilised through dolerite intrusions.

QAQC

Quality assurance and quality control.

Quality or Grade

An informal classification of coal relating to its suitability for use for a particular purpose. Refers to individual measurements such as heat value (CV); fixed carbon; moisture; ash; sulphur; phosphorus; major, minor, and trace elements; coking properties; petrologic properties; and particular organic constituents. The individual quality elements may be aggregated in various ways to classify coal for such special purposes as metallurgical, gas, petrochemical and blending usages. Grade is inversely related to the percentage of inorganic material in the coal and is largely determined during the depositional stage of the coal’s formation. The ash content of a coal is therefore the most convenient measure of its grade.

Domestic market coal is South Africa has traditionally been classified as “A”, “B”, “C” or “D” grade coal, graded by calorific value (CV).

R or Rand

The South African rand, the lawful currency of South Africa.

Rank

The classification of coal relative to other coals, according to their degree of metamorphism, or progressive alteration, in the natural series from lignite to anthracite (Standard Classification of Coal by Rank, 1992, American Society for Testing and Materials, ASTM Designation D-388-91a). The rank of a coal refers to the degree of metamorphism it has undergone, which results from increases in temperature and pressure subsequent to burial. Metamorphism causes a change in the chemical composition, and physical-chemical properties of the organic matter. The properties of the maceral vitrinite are used to quantify the rank of the coal.

RB1

Coal with the following specifications:

- calorific value: basis 6 000 kcal/kg NCV, minimum 5 850 NCV;

- total moisture: maximum 12% (as received basis);

- volatile matter: minimum 22% (as received basis);

- ash: maximum 15% (as received basis);

- sulphur: maximum 1.00% (as received basis);

- hardgrove grindability index: 45-70 (typical, and not to be used for determining whether or not a shipment complies with the specification);

- nominal top size: 50 millimetres;

- ash fusion temperature (initial deformation): minimum of 1 250 degrees Celsius in a reducing atmosphere;

- calcium oxide in ash: maximum 12% (dry basis).

RB2

coal with the following specifications:

- calorific value: basis 6 000 kcal/kg NCV, minimum 5 850 NCV;

- total moisture: maximum 12% (as received basis);

- volatile matter: minimum 25% (as received basis);

- ash: maximum 15% (as received basis);

- sulphur: maximum 1.00% (as received basis);

- hardgrove grindability index: 45-70 (typical, and not to be used for determining whether or not a shipment complies with the specification);

- nominal top size: 50 millimetres;

- ash fusion temperature (initial deformation): minimum of 1 250 degrees Celsius in a reducing atmosphere;

- calcium oxide in ash: maximum 12% (dry basis).

RBCT

The Richards Bay Coal Terminal.

RD

Relative Density.

RoM

Run-of-Mine.

Roofbolt

A long steel bolt inserted into walls or roof of underground excavations to strengthen the pinning of rock strata.

SA or South Africa or RSA

The Republic of South Africa.

SAMREC

The South African Mineral Resource Committee.

SAMREC Code

The South African Code for Reporting of Mineral Resources and Mineral Reserves including the guidelines contained therein.

SANS

South African National Standards.

Seam

A bed of coal lying between a roof and floor; an equivalent term to bed, commonly used by the industry; alternatively a provincial term for a coal bearing layer.

Seam Drive

An excavation driven within the plane of the orebody.

SENS

The Securities Exchange News Service of the JSE.

Servitude

A right that grants use of another’s property.

Short-Life

Operation of with less than 5 years.

Sidewalls

The sides of an excavation.

Sill

A concordant sheet of igneous rock lying nearly horizontal. A sill may become a dyke or vice versa.

Sinks

Material during the testing or washing process that sinks to the bottom of the testing or washing medium; generally forming the waste or discard fraction.

Sloughing

The action of soft material when wet; generally associated with the failure of soft material stockpiles.

SLP or Social and Labour Plan

A document that is submitted in terms of MPRDA and the Mining Charter as part of an application for a Mining Right.

MWP or Mine Works Programme

A document that is submitted in terms of MPRDA and the Mining Charter as part of an application for a Mining Right.

DALA

The Mpumalanga Provincial Department of Agriculture and Land Affairs.

Spalling

Failure of the highwall, generally caused by poor blasting practices, weathering or ingress of water.

Spirals

Equipment used in the washing of coal; used to separate fine waste from a fine coal/waste mixture.

Strike

The course or bearing of the outcrop of an inclined bed, vein, or fault plane on a level surface; the direction of a horizontal line perpendicular to the direction of the dip.

Sulphur Content or Sulphur

sulphur may be present in three forms in coal, namely as sulphide, sulphate and organic sulphur. Sulphur is undesirable in metallurgical coal, and also causes various environmental problems.

t

Tonnes.

Tailings

The gangue and other refuse material resulting from the washing, concentration, or treatment of ground ore.

Thickening

The concentration of the solids in a suspension with a view to recovering one fraction with a higher concentration of solids than in the original suspension.

Total Cash

Cost incremental components to cash costs including royalties but excluding taxes paid.

Total Costs

The summation of total working costs, net movement in working capital and capital expenditure.

Total Working Cost

Incremental components to total cash costs including terminal separation benefits, reclamation and mine closure costs (the net difference of the total environmental liability and the current trust fund provision) but excluding non cash items such as depreciation and amortisation.

Transgressive

Term used to describe dolerite intrusions into the coal seams.

Type

Refers to the maceral composition of a coal and is determined by the nature of the original plant material and its degree of alteration during the process of diagenesis.

Unredeemed Capital

Capital expenditure which may be offset against future profits to lessen the taxable profit.

ST

Short (US) ton = 907.19 kilograms = 2 000 lb. This measure of mass is not used in South Africa.

VAT

Value-added tax payable in terms of the South African Value-Added Tax Act, No 89 of 1991.

Volatile Matter or Vols

defined as the material (other than inherent moisture), which is driven off when air-dried coal is heated at 900 degrees Celsius for seven minutes under standard condition, in the absence of air.

Vryheid Formation

Stratigraphic sequence in Southern Africa containing coal deposits.

Washability

Ability of the coal to be separated from waste fractions at a range of relative densities.

Washability Analysis

Analysis to determine the coal behaviour and separation characteristics for a range of relative densities.

Washing or Coal Preparation

Is the treatment of coal to reject waste. In its broadest sense, preparation is any processing of mined coal to prepare it for market, including crushing and screening or sieving the coal to reach a uniform size, which normally results in removal of some non-coal material. The term coal preparation most commonly refers to processing, including crushing and screening, passing the material through one or more processes to remove impurities, sizing the product, and loading for shipment. Many of the processes separate rock, clay, and other minerals from coal in a liquid medium; hence the term washing is widely used. In some cases coal passes through a drying step before loading.

Water Use Licence

A licence issued by the regulatory authority governing the abstraction, use and discharge of water.

Weightometer

An appliance for the continuous weighing of broken ore material in transit on a belt conveyor.

Working Capital

Expenditures required to fund the resulting change in the debtors, creditors and stores position at a point in time.