Istilah-Istilah Analisa Cadangan

8/18/2019 Istilah-Istilah Analisa Cadangan

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Analisa cadanganDepartemen Teknik Pertambangan - ITM

Edy Yasa Ardiansyah,Ir.MT 1

Modul 3Istilah –Istilah dalam Analisa Cadangan

The credibility of database and geological interpretations are moreimportant than the methodology used for estimates. Database credibility depends

on the sampling and sample preparation procedures and on the adequate andreliable analyses as described in previous chapters. Geological interpretations

should include a credible evaluation of the database and adequate models derivedfrom the processing of data.

Three important principles should be realized:

1. All the phases of estimation must be transparently documented so

that the grounds for all choices and all conclusions are visible as well as themethods of research and calculations. No 'black boxes' are to be accepted.

2. When something is outlined, the framework must be described as well.So, when a mineral deposit is outlined, the criteria for separating thedeposit material from the geological frames, their structures, lithology, andgrades, must be presented. Also all information supporting shape, size andstructure interpretations should include a reference to a larger geologicalframework.

3. All estimate methods have their faults and shortcomings. For the best

result, at least three basically different methods should be applied foreach estimation. A reasonable sensitivity analysis of parameters should beapplied to each case.

1 Terms and definitions

BLOCK ESTIMATE METHODSThey base on block models of a mineral deposit, either on bench by bench (2D)models or on real 3D models. The deposit space is subdivided into amatrix of blocks whose dimensions are governed by the mining method

chosen as well as the geology and the sampling network of the deposit. If theblocks are similar in size and shape, any 2D spatial statistics can be used tointerpolate blocks bench by bench while benches may be defined in threedifferent directions (XY, XZ, YZ). Real 3D models demand, respectively, 3Dstatistics which is much more difficult to handle than the former. On the otherhand, when properly applied, they give better results.


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CORE LOSS ( / core recovery)Soft, non-coherent rock may flow out from the hole leaving empty spaces inbetween hard rock samples. These spaces are core loss. Core loss locationsshould be marked accurately as if they were samples. Core loss data may lead

to important structural information. Statistical core loss is usually expressed inpercentages per meter or per hole. Sometimes core recovery is used insteadof core loss. It means the amount of core in percentages that has beencollected.

COUNTRY ROCK (wall rock, mother rock)Country rock means the rock next to the ore and its host, or the rock enclosingor traversed by a mineral deposit. Data of country rock is valuable since mostof the dilution comes from country rock.

CUTOFF GRADE (analytical cutoff, geological cutoff, economic cutoff,monetary cutoff )Economic cutoff grade means the lowest grade of mineralizedmaterial that qualifies as ore. Analytical cutoff means the lowestgrade accepted to be processed or estimated . In a mine there may be ageneral cutoff grade for an element but several subcutoffs for subprocesses likeone for blasting, one for loading, one for transporting further than 1 500 m,etc. These are economic cutoffs. Simultaneously they are analytical cutoffs.However, in a broad sense of this term, analytical cutoff may be a lower gradelimit on any other but economic ground as well.

Cutoff grades are normally expressed in percentages of metal for base metalsand in grams per metric tons or ounces per short ton for precious metals.Cutoff grades may be simple or compound. In cases where the numberone metal (or rather the refinery) is clearly defined, all other metals can beincluded in the compound cutoff grade. It is then called an equivalent grade,for example (Wrigglesworth, 1995):

%Eq.Ni = %Ni + {(Cu price)* %Cu/(Ni price)}

%Eq.Zn = 1.6*Cu% + 0.1*Pb% + Ag/55 g/t - 2.5%.

The latter formula obviously contains some 'experience factors' (1.6, 0.1, 55and 2.5). Normally the metal price referred cannot be a market price since veryfew mines sell their product, the concentrate, anywhere else but to a certainsmelter or refinery. The real price for the product will be negotiated with thebuyer of concentrates.Instead of grades, used in analytical cutoff expressions, other terms may be


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used. In some cases, the lithological or structural constraints of an ore body areso clear that cutoff grades may be replaced by geological definitions. Mining orprocess technical reasons may lead to similar solutions. Instead of grades,monetary units may be used. However, simple cutoff grades for each

valuable metal or mineral should be the basis of resource and reserveestimates. Fig. 36 illustrates problems in commanding drill core classificationproblems with a given cutoff grade.

CUTTING FACTORCutting factor is the highest metal assay accepted in resource/reserveestimates. Any individual assay value above the cutting factor is reduced to thelatter. The cutting factor either base on the experience gained through themining and processing of the same or similar type material, as is the target ore,or it is based on mathematical reasoning. Cutting factor is comparable to the'nugget effect' and, similarly, used for gold ore estimates. There should not be

anything like that but, due to inadequate sampling or sample preparation,measured values must be reduced.

DETAILED EXPLORATION (inventory drilling)This includes the three dimensional delineation and sampling of a known targetfrom outcrops, trenches, a systematic set of boreholes, from shafts andtunnels, including bulk sampling (pilot mining) for processing tests (pilot tests).The sampling grid is spaced so closely that size, shape, grade andother relevant characteristics of the target are established with a highdegree of accuracy and in sufficient detail for mine planning.

DILUTION (waste rock dilution)Dilution may come from internal waste, planned waste (intentionaldilution), accidental waste or geologic waste. Internal waste, whendetected, is usually included at assay grade. Planned waste is what belongs tothe stopes to be mined. It can be foreseen and thus it can be added to the orereserve estimation at the assayed grade; it usually varies from 10 % to 40 %.

Accidental waste is a surprise caused by cavings, slough, etc. It may be causedby the incomplete control on the rock mechanics of a mine or by unrecognizedzones of weakness. Geologic waste is caused by the incomplete knowledge onthe shape of ore bodies. Contacts are usually interpolated from drill hole to drill

hole. What happens between holes is not necessarily easy to predict: a problemwith sampling density! Technical reasons may lead to faulty conclusions. Forexample the sample positions, due to the inadequate or badly documented holeorientation, may not be true.

Waste dilution is normally expressed using the formula:

Waste dilution = the percentage of waste in the feed.


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EFFECTIVE GRADEThe apparent grade averaged to a deposit may be true but misleading.The effective grade is generally lower than the apparent one, seldom higher.

The former is counted on the basis of the material that will be really enriched. All calculations of ore loss, dilution and recovery derive from the knowneffective grade. Since we usually concentrate minerals and not metals, weshould pay attention to the analytics (and sampling, of course). If the samplesare representative, they contain real ore material in quantities and ratios thatcorrespond to the material to be fed in the concentration plant. Respectively,analyzing methods should be relevant. For example, Ni should be analyzed bybromine methanol method to not include silicate nickel in the grade.

EQUIVALENT (cutoff )See cutoff.

EXPLORATION INFORMATION (mineral potential)Information that results from activities designed to locate mineral deposits. Thisincludes regional information and information of any non-minable mineraloccurrences. It may be also called mineral potential if it is considered worthy offurther investigation.

EXTRACTION RATIO (mine recovery)The proportion of the total in situ reserve that is actually extracted duringstoping.

FEASIBILITY STUDY (pre-feasibility study, tentative F.B.) A feasibility study forms the basis for the investment decision. See Figs. 7 and44. The result must be reasonably accurate, with usually +- 10 % error.

A pre-feasibility study follows the structure of F.S. but may be based more ondefault values and simulations than the former (error limits of less than +- 50%). Respectively, tentative feasibility studies may be used at early projectphases to justify further investigations. See Geological study and Fig.4.

FEEDFeed is the mined material that is transported to the concentration plant for

enrichment. In practice an ore reserve estimate means a grade and tonnageestimate of the average feed(s).

FINANCIAL MODEL (economic model)Usually it includes DCF (discounted cash flow model), IRR (internal rate of returnsmodel) andpay back time calculation with a sensitivity analysis.


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GANGUE (matrix)The valueless rock in a ore body or in an ore sample.

GENERAL EXPLORATION (preliminary target investigation, screening)It involves the initial delineation of an identified target mostly by surface mapping,loose-grid sampling (drilling), and limited interpolation based on indirect methodsof investigation, to establish general geological features and to provide an initialestimate of size, shape and grade. Results are adequate for deciding whetherdetailed exploration is warranted (Figs. 4, 7).

GEOLOGICAL STUDY (pre-investment study, opportunity study, screening) A G.S. forms a preliminary evaluation, and it is aimed at identifying a possiblemineral resource investment opportunity. Due to the preliminary character of thisinvestigation, the error limits are usually greater than +- 50 %. A geological study

is often connected with an economic model study that addresses the followingitems:

- mineralreserve/resource

- capital costestimate

- mining - operating cost estimate

- processing- financial analysis. See Figs.4, 7.

HOST ROCK

The rock hosting an ore: especially with low-grade ores host rock and itsproperties are important to know and to control.

MINERAL DEPOSIT A general name for an outlinable and quantifiable natural mineral enrichmentpossibly of economic value.

MINERAL OCCURRENCE (mineral showing)Mineral enrichment not quantified nor otherwise evaluated. Also: a minor mineraldeposit of no or minimum value, though possibly prognostically interesting.

MINERAL RESOURCE (measured, indicated, inferred)

A mineral resource is an accumulation of material of intrinsic economic interest insuch form and quantity that economic exploration of a mineral from the depositmay be feasible.

A measured mineral resource has been explored, sampled and tested (lab.scale) through appropriate techniques with observations and samples spaced


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closely enough to confirm geological continuity. The data should allowtonnage/volume, densities, size, shape, quality, mineral content and grades to beestimated with a high level of certainty.

An indicated mineral resource is defined like above except that samples aretoo widely spaced to confirm geological continuity but they are spaced closelyenough to assume geological continuity.

An inferred mineral resource is indirectly or, without systematic sampling,assumed to be a part of a total mineral resource.For different definitions, see Fig. 37. For a discussion see Appendix 1.

MINIMUM MINING DIMENSIONS (width, height)Minimum dimensions depend on the mining technique chosen and they may varyfrom deposit to deposit or even from body to body in a single deposit. They areexpressed as horizontal and vertical widths or heights. When expressing deposit

dimensions geologists often use true dimensions. However, if a deposit is nothorizontal or vertical but inclined, this may lead to different results in estimates. Itusually means ore loss and waste rock dilution to change the reference systemfrom that of the true deposit to the horizontal or vertical structures demanded by amining operation.

NUGGET Technically, nugget is the name for the departing of the modeled variogram curvefrom the origin (or the zero point). In practice it means a lowered reliability ofsample analyses due to the uneven or sparse distribution and/or large grain size of

minerals hosting assayed elements. Nugget was first recognized when analyzinggold samples - and it was explained to be caused by the nuggety appearance ofgold in large and random grains. Nugget or 'the nugget effect' may give a measureto optimize geological sampling or sample preparation.

OREEconomically valuable enrichment of mineral(s). Also: mineralized rock type that istypical to economic mineral deposits.

OREBODY A three dimensional continuous mass of ore, either an ore deposit or an outlined

part of an ore deposit. Also: a technically definable unit of an ore deposit.

ORE LOSSThe part of an orebody (in percentages) that is not blasted or loaded during amining process. Usually this happens because of unexpected outlines of ore or as aconsequence of unsuccessful blasting. Instead of ore loss, ore recovery may beused.


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ORE MINERALThe essential, and usually smallest constituent of ore to be enriched.

ORE RESERVE (proved, probable)The economically minable part of a mineral resource, inclusive of diluting materialsand allowing for losses.

A proved ore reserve is that part of measured mineral resource that canbe exploited.

A probable ore reserve is that part of measured or indicated mineralresource that can be exploited under appropriate technical and economicconditions.

ORE VALUEOre value is the value of mineral concentrate per ore ton. The price or value

of concentrate depends on the agreement between mine and refinery (smelter).

PARAMETER (factor, coefficient, 'experience factor')'Quantity constant in case considered, but varying in different cases' (Fowler's,1989).Other terms related to 'parameter' are 'factor' and 'coefficient'. Parameter isusually a mathematically derived number but in geology there are several'experience factors'.

POLYGON ESTIMATE METHODS (triangulation)

The grade and thickness of each hole penetrating a plane can be assigned to anirregular polygon. These are assumed to remain constant throughout the area ofthe polygon that can be defined on the basis of perpendicular bisectors or angularbisectors. Figs 22 - 23. Triangulation is a simplified (though a very powerful) typeof polygonal methods. Fig 21.

PROSPECTION (target identification)It is the systematic process of searching for an unknown deposit based on geologicinference and/or postulation of extensions of known deposits, by outcropidentification and indirect methods. The objective is the discovery of aprospect that will be the target for further exploration.

RECONNAISSANCE (identification of mineralized areas or zones)The process of narrowing down areas of enhanced mineral potential on a regionalscale based primarily on airborne and indirect methods, preliminary field inspectionas well as geological inference and extrapolation. The objective is to identifymineralized areas for further investigation towards prospect identification.


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RECOVERY (mining recovery, concentration recovery, metallurgical recovery)The percentage of valuable minerals derived from an ore at a stage of mining:blasting R, loading R, concentration R, smelter R, etc. Mining recovery usuallycovers most of these phases and defines the recovery of a mineral derived

into a concentrate.

RESOLUTION (GIS, graphic presentations)The level of object detail or sharpness determined by how many picture elementscompose an area of a display or corresponding raster. Ground resolution is thelimit of detail clarity in an image of the earth's surface.

SECTIONAL ESTIMATE METHODS (linear and standard sectional methods) An estimation method based on the connection of representative points of adelineated deposit on different cross sections. Resembles polygonal method but isbased on geological (or on equal value contours) rather than mathematical

outlining of polygons. In an ideal case sections are cut perpendicular to the longaxis of a deposit and the continuation of geologically identifiable bodies can bedemonstrated from a section to another. In linear sectional method blocks aredrawn perpendicular to the sections and ended in the middle of sections.

In standard sectional method blocks are formed by connecting respectivepoints with each other straight from section to section. While this is a more'natural' method, it is more difficult for a manual estimate. On the other hand,computer applications favor this method that leads straight to 3D solid modeling.

SPATIAL DATASpatial data is composed of data points with specific X, Y and Z coordinates and ofcorresponding data values representing any (geological) feature: grade, density,rock-type, etc.

TAILINGSSand, at the moment non-saleable product of concentration, usually stored forpossible future needs.

TONNAGE FACTORS (bulk density)Specific gravity is one of the standard petrophysical measurements for drill core

samples. However, for large rock masses, specific gravity gives too high values. Inrock there is void space, cavities, open fractures, porosity, etc., that reduces itsoverall density. Therefore, bulk density or tonnage factor should be estimated andused in resource/reserve calculations. Bulk density or tonnage factor isdefined as 'mass per unit volume'. Geophysicists may make this revisionautomatically.


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Tintaya Mine, BHP Billiton Tintaya S.A., 2000: Review the ore reservemodelling methodology and design DDH patterns to prove the ore reserves atseveral satellite deposits.

Diavik, Diavik Diamond Mines, NT, Canada, 1999: Implementation ofconditional simulation for the estimation of diamond resources.

Monywa, Ivanhoe Holdings, Myanmar, 1996-1997: Member of the MRDI

feasibility study team for a copper heap leach project.

Turquoise Ridge, First Miss Gold, NV, USA, 1995: Member of the MRDIfeasibility study team for vein gold.

Radomiro Tomic, Codelco Chile, 1998: Extensive review of the long term orereserve model for the purposes of improving prediction accuracy and increasingconfidence in the ore reserve model for expansion plans.

Chuquicamata, Codelco Chile, 1998: A study on the impact of variable bench

height on minable reserves as part of a larger engineering feasibility study for theexpansion of mining operations.

Chuquicamata, Codelco Chile, 2000: An extensive review of the Chuquicamatalong term ore reserve model for the purposes of improving local accuracy for longterm mine planning and expansion studies. Also updated the Moly model.

Chuquicamata, Codelco Chile, 1997: An extensive review of the transitionzone - low grade sulfide ore reserve model for the purposes of resolving a majorreconciliation problem between model predictions and production figures.

Confidential Acquisition Target, Codelco Chile, 1999: Due diligence study onthe geologic and mineral resource model for a possible acquisition target.

North Oxides, Chuquicamata, Codelco Chile, 1998: A review of the geologicmodel using geostatistics and indicator kriging. The objective was to prepare ageologic model with unbiased geologic units in terms of contained ore tonnages.


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Radomiro Tomic, Codelco Chile, 1997: The design of a mine plan for theseparation of three oxide ore types at the time of mining. The design was basedon a conditional simulation model of the oxide ore types at Radomiro Tomic.

Radomiro Tomic, Codelco Chile, 1998: Provided a geostatistical assessment ofthe uncertainty associated with predicting minable reserves at Radomiro Tomic.

Radomiro Tomic, Codelco Chile, 2000: Review of the short term mineplanning ore reserve model for the purposes of resolving a reconciliation problembetween the model predictions and production.

San Antonio Project, Codelco Chile, 1997: Audit of copper resource models.

Agua Rica Deposit, BHP, Argentina 1998: Prepared the ore resource modelfor a pre-feasibility study of the Agua Rica Copper and Molybdenum Deposit in

Argentina.

Robinson Copper-Gold Deposit, BHP, Nevada, 1996: Technical review of thegrade control procedure for the purposes of reconciling differences between theshort term model predictions and production figures.

San Manuel Copper Deposit, BHP, Arizona, 1996: Technical review of theunderground ore reserve model.

Florence copper deposit, BHP, Arizona, 1996: Technical review of the oreresource model for a proposed in-situ leach project.

Sur Sur Deposit, Andina Mine, Codelco Chile, 1997: A Geostatistical reviewof the Sur Sur copper ore reserve model for the purposes of reconciling productionfigures with model grade estimates.

Mary-Drinkwater Deposit, Mineral Ridge Resources Inc.1995: Preparedthe pre-feasibility gold ore resource model for Mineral Ridge. This work was donethrough MRDI.

Meikle Deposit, Barrick Goldstrike, Elko, Nevada 1998: Variography and

conditional simulation of the Meikle deposit to evaluate and confirm productionschedules.

RoseBud Mine, Hecla Mining, 1998: Technical review of the ore reserve model(gold deposit), re-did the variography and implemented geostatistical methods forore reserve modelling and estimation.


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Lucky Friday Mine (poly-metallic), Hecla Mining, 1998: Design of adiamond drill pattern for the purposes of enabling the classification of miningreserves as proven and probable.

Gold Hunter South Vein, Hecla Mining, 1998: Technical Review of currentmethodology used to prepare ore reserve model and implemented new estimationmethods.

Meridian Gold Project, Standard Bank of London, 1999: Due diligenceevaluation of a potential acquisition target by the Meridian Gold Project.

Ray Mine, Asarco Inc., 2000: Technical review and re-calculation of orereserves using conditional simulation.

BaseloadThe minimum amount of electric

power delivered or required over agiven period of time at a steady

rate.

CanduCanada, Deuterium, Uranium.Canadian designed and built

pressure-tube nuclear reactorwhich uses natural uranium as fueland heavy water (deuterium oxide)

as the moderator.

Contangohe positive difference between thespot market gold price and theforward market gold price. It is

normally expressed as a per-annuminterest rate and is the differencebetween London Inter Bank OfferRates (LIBOR) and the lease ratecharged by institutions that lend

gold.

Conversion Factors

U3O8 Triuranium octoxide. At Camecooperations, it is in the form of

concentrate, often calledyellowcake.

UF6 Uranium hexafluoride. Convertedfrom U03 at Cameco's Port Hope

plant. Following enrichment, UF6 isconverted to enriched U02 suitablefor fabrication into fuel for light-

water reactors.

Western World Uranium MarketWestern world includes Argentina,

Australia, Belgium, Brazil, Canada,Czech Republic, Finland, France,

Gabon, Germany, India, Indonesia,Japan, Mexico, Namibia,

Netherlands, Niger, Pakistan,Philippines, Portugal, Romania,Slovenia, South Africa, South

Korea, Spain, Sweden, Switzerland,Taiwan, Thailand, Turkey, United


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Weights and measures areindicated in the unit most

commonly used in specific areas ofthe industry. These are noted with

* and conversion factors areprovided below.

TakeThis:

Do This To ObtainThis

*cm ÷ 2.54 = inch

*km ÷ 1.60 = mile

*oz x 31.10 = g

t x 1.10 = T

*T x 0.90 = t

*oz/T x 34.28 = g/t

*lb U3O8 ÷

2599.8

= tU

tU x 2599.8 = lb U3O8

*% U3O8 ÷ 1.18 = % U

DoseTerm used to quantify the amountof energy absorbed from ionizing

radiation per unit mass.

Electricity Measurements1kW x 1000 = 1MW x 1000 =

1GW x 1000 = 1TW

Kilowatt (kW): kilowatt-hour(kWh)

Kingdom and the United States.

Reserves and Resources

Mineral Resource A mineral resource is a

concentration or occurrence ofnatural, solid, inorganic or fossilized

organic material in or on theEarth's crust in such form and

quantity and of such a grade orquality that it has reasonable

prospects for economic extraction.The location, quantity, grade,

geological characteristics andcontinuity of a mineral resource are

known, estimated or interpretedfrom specific geological evidence

and knowledge.

Inferred Mineral Resource An inferred mineral resource is thatpart of a mineral resource for whichquantity and grade or quality can

be estimated on the basis ofgeological evidence and limited

sampling and reasonably assumed,but not verified, geological and

grade continuity. The estimate isbased on limited information and

sampling gathered throughappropriate techniques fromlocations such as outcrops,

trenches, pits, workings and drillholes.

Indicated Mineral Resource An indicated mineral resource isthat part of a mineral resource forwhich quantity, grade or quality,


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A kilowatt is a unit of powerrepresenting the rate at which

energy is used or produced. Onekilowatt-hour is a unit of energy,

and represents one hour ofelectricity consumption at a

constant rate of 1kW.

Megawatt (MW): megawatt- hour (MWh)

A megawatt equals 1000 kW. Onemegawatt-hour represents one

hour of electricity consumption at aconstant rate of 1MW.

Gigawatt (GW): gigawatt-hour(GWh)

A gigawatt equals 1000 MW. Onegigawatt-hour represents one hour

of electricity consumed at aconstant rate of 1GW.

Terawatt (TW): terawatt-hour(TWh)

One terawatt equals 1000 GW. Oneterawatt-hour represents one hour

of electricity consumption at aconstant rate of 1TW

Enriched UraniumUranium in which the content of

the isotope uranium-235 has beenincreased above its natural value of

0.7% by weight. Typical low-enriched uranium for commercial

power reactors is enriched inuranium-235 to the range of 3% to5%. In highly enriched uranium,

the uranium-235 has beenincreased to 20% or more.

density, shape and physicalcharacteristics, can be estimated

with a level of confidence sufficientto allow the appropriate application

of technical and economicparameters, to support mine

planning and evaluation of theeconomic viability of the deposit.

The estimate is based on detailedand reliable exploration and testing

information gathered throughappropriate techniques fromlocations such as outcrops,

trenches, pits, workings and drillholes that are spaced closely

enough for geological and gradecontinuity to be reasonably

assumed.

Measured Mineral Resource A measured mineral resource isthat part of a mineral resource for

which quantity, grade or quality,density, shape and physicalcharacteristics are so well

established that they can beestimated with confidence sufficientto allow the appropriate application

of technical and economicparameters, to support production

planning and evaluation of theeconomic viability of the deposit.

The estimate is based on detailedand reliable exploration, samplingand testing information gatheredthrough appropriate techniquesfrom locations such as outcrops,trenches, pits, workings and drill

holes that are spaced closely


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In Situ Leaching A process involving pumping asolution down an injection well

where it flows through the deposit,dissolving uranium. The uranium-

bearing solution is pumped tosurface where the uranium isrecovered from the solution.

Light Water Reactor A thermal reactor using ordinarywater both as a moderator and asa coolant with enriched uranium as

fuel.

Ounce (oz) All ounces in this report are troy

ounces.

RadiationRadiation occurs naturally. It is a

type of energy that travels throughspace in the form of waves, or

particles, which give up all or partof their energy on contact with

matter. Radiation can take the formof alpha or beta particles, X-rays or

gamma rays, or neutrons.

Radiation Types Alpha particles do not penetrate

matter deeply. They can bestopped by a sheet of paper or a

few millimetres of air. The potentialhazard from alpha particles is

internal from possible inhalation oringestion.

Beta particles penetrate furtherthan alpha particles but can be

stopped by aluminum foil or a few

enough to confirm both geologicaland grade continuity.

Mineral Reserve

A mineral reserve is theeconomically mineable part of ameasured or indicated mineral

resource demonstrated by at leasta preliminary feasibility study. This

study must include adequateinformation on mining, processing,metallurgical, economic and otherrelevant factors that demonstrate,

at the time of reporting, thateconomic extraction can be

justified. A mineral reserve includesdiluting materials and allowances

for losses that may occur when thematerial is mined.

Probable Mineral Reserve A probable mineral reserve is theeconomically mineable part of an

indicated, and in somecircumstances a measured mineralresource demonstrated by at leasta preliminary feasibility study. This

study must include adequateinformation on mining, processing,metallurgical, economic, and otherrelevant factors that demonstrate,

at the time of reporting, thateconomic extraction can be

justified.

Proven Mineral Reserve A proven mineral reserve is theeconomically mineable part of a

measured mineral resourcedemonstrated by at least a


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centimetres of wood.

Gamma rays penetrate most deeplyand substances which emit gamma

radiation can be hazardous insideand outside the body. Protection

from gamma rays includes shieldingby concrete, water and lead.

Neutrons are particles which alsopenetrate matter deeply. They

come from outer space and alsooccur inside nuclear reactors.Water and concrete are used

effectively as shielding in nuclearplants.

RadonRadon is a naturally occurring,

radioactive gas that is producedfrom the radioactive decay ofradium-226, one of the decayproducts of uranium-238. The

primary hazard from radon is itsdecay products, which are referred

to as radon progeny. Radonprogeny are short-lived radioactive

decay products of radon gas.

Spot Market PricePrice for product sold or purchased

in the spot market rather thanunder a long-term contract.

for electricity he buying and selling of electricity

for immediate delivery.

for U 3 O 8 and UF 6 conversionservices

The buying and selling of uranium

preliminary feasibility study. Thisstudy must include adequate

information on mining, processing,metallurgical, economic, and otherrelevant factors that demonstrate,

at the time of reporting, thateconomic extraction is justified.

Notes

In this mineral reserves andresources statement Cameco uses

a definition of classes of

mineralization taking into accounta maximum number of parametersof various natures.

These parameters are:

• the precision of theestimate;

the economic feasibility ofthe project, which relates not only

to grades but to the volume of thereserves, the location, thechemistry of the expected ore, the

price of the product, etc.;• the legal status of theproject and its possible evolution in

the very near future.Cameco's mineral reserves includeallowances for dilution and miningor in situ leaching recovery, except

for the McArthur River reserveswhere the high-grade ore requiresdeliberate dilution to comply withlicence conditions. No allowances

have been applied to mineralresources. Stated mineral reserves

and resources have been


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products for delivery within oneyear.

t

Tonne (metric ton)

TTon (short ton)

U02 Uranium dioxide. Converted fromU03 at Cameco's Port Hope plant,then compressed to pellets and

sintered by fuel fabricators to make

fuel for Candu reactors.

U03 Uranium trioxide. An intermediate

product produced at Cameco'sBlind River refinery and used asfeed to produce U02 and UF6 atCameco's Port Hope conversion

plants.

calculated based on estimatedquantities of mineralized materialrecoverable by established mining

methods. This includes onlydeposits with mineral values inexcess of cut-off grades used in

normal mining operations.Cameco's mineral reserves includematerial in place and on stockpiles.

Only mineral reserves havedemonstrated economic viability.

There are numerous uncertainties

inherent in estimating mineralreserves and resources. Theaccuracy of any reserve and

resource estimation is the functionof the quality of available data and

of engineering and geologicalinterpretation and judgment.

Results from drilling, testing andproduction, as well as material

changes in uranium or gold prices,

subsequent to the date of theestimate, may justify revision of

estimates.

Cameco's classification of mineralreserves and resources and the

subcategories of each, conforms tothe definitions adopted by CIM

Council on August 20, 2000, whichare incorporated by reference intothe National Instrument 43-101

dated November 17, 2000, issuedby the Canadian Securities

Administrators. Cameco reportsreserves and resources separately,the amount of reported resourcesdoes not include those amounts


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identified as reserves. Mineralresources which are not mineral

reserves do not havedemonstrated economic viability

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