Mineral Resource and Reserve aspects of the Junior … Resource and Reserve aspects of the Junior...

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Mineral Resource and Reserve aspects of the Junior Miners on the Bushveld ComplexKen Lomberg

Extraordinary PeopleExtraordinary Outcomes

Majors - Historically• Anglo Platinum• Impala• Lonmin

Mid Tier - Producers• ARM• Aquarius Platinum• Eastplats• Northam• Xstrata

So what is a Junior Explorer?

Canadian Definition of a Junior Explorer

• No significant income from mining or other business• Funding not from previous production or investments• Funding not from single majority holding company• Principal funding from seed capital or issue of shares• Not exploration arm of a major company• Not a primary producer• Not a government organisation

ExplorationPre-

development Capex Production

Private equity funds, hedge funds

Private equity funds, hedge

funds, general public

Institutions, general public, banks

Inferred

Indicated

Measured

Probable

Proven

Pre-inferred

ResourcesBFSPFS

Juniors MajorsD

isco

very

Reserves

Ope

ratio

ns

Crossover

Junior Companies

• Platfields• Platmin• Platinum Australia• Platinum Group Metals• Platinum Mining Ventures • Ridge Mining• Sephaku• Sylvania Resources• Wesizwe Platinum

• AIM Resources• Anooraq• Barrick • Bushveld Platinum• Caledonia Mining• Eastern Platinum• Ivanplats• Jubilee Platinum• Lesego Platinum• Nkwe Platinum• Pan Palladium

ExplorationPre-

development Capex Production

Private equity funds, hedge funds

Private equity funds, hedge

funds, general public

Institutions, general public, banks

Inferred

Indicated

Measured

Probable

Proven

Pre-inferred

ResourcesBFSPFS

Juniors MajorsD

isco

very

Reserves

Ope

ratio

ns

Project Maturity

Need for accuracy at/above cut-off

Need for low level assay sensitivity

The Bushveld Complex

Economic Horizons• Merensky Reef• UG2 Chromitite Layer• Platreef• Other?

NORTHERN LIMB

FAR WESTERNBUSHVELD COMPLEX

f

f

ff

f

f

f

f

f

f

f

RUSTENBURG

BELA-BELA

Kookfontein upfold

PRETORIA

JOHANNESBURG

Spruitfontein upfold

Wolhuterskop

Pilanesberg Complex

Gap areas

0 20 40 60 80 100 km

-25°

25°-

26°-

24°-

WESTERNBUSHVELD COMPLEX

MOKOPANE

MIDDELBURG

Steelpoort fault

EASTERNBUSHVELD COMPLEX

Wonderkop fault

Kalkloof anticline

Schwerin foldDerdegelid pericline

Steelpoort pericline

BURGERSFORT

30° I

29° I

28° I

27° I

26° I

f

N

f

f

f

f

I

29°

I

28°

I

27°

Lower, Main and Upper Zone

Critical Zone

fFold axisFault

f

I

26°

-24°

I

30°

Brits Graben

f

f

ff

f

f

f

f

f

f

f

RUSTENBURG

BELA-BELA

Kookfontein upfold

PRETORIA

JOHANNESBURG

Spruitfontein upfold

Wolhuterskop

Pilanesberg Complex

Gap areas

0 20 40 60 80 100 km

- 25° 25° -

WESTERNBUSHVELD COMPLEX

28°I

27°I

26°I

I

28°I

27°

f

Brits Graben

Lower, Main and Upper Zone

Critical Zone

fFold axisFault

Northam

Amandelbult

Union

BRPM

Impala

Rustenburg Lonmin

Eastplats

Elands

Aquarius

f

f

ff

f

f

f

f

f

f

f

RUSTENBURG

BELA-BELA

Kookfontein upfold

PRETORIA

JOHANNESBURG

Spruitfontein upfold

Wolhuterskop

Pilanesberg Complex

Gap areas

0 20 40 60 80 100 km

- 25° 25° -

WESTERNBUSHVELD COMPLEX

28°I

27°I

26°I

I

28°I

27°

f

Brits Graben

Lower, Main and Upper Zone

Critical Zone

fFold axisFault

De Wildt

Madibeng

WesizweWBJV

PilanesbergSedibelo

Rooderand

Pandora

NORTHERN LIMB

FAR WESTERNBUSHVELD COMPLEX

f

f

ff

f

f

f

f

f

f

f

RUSTENBURG

BELA-BELA

Kookfontein upfold

PRETORIA

JOHANNESBURG

Spruitfontein upfold

Wolhuterskop

Pilanesberg Complex

Gap areas

0 20 40 60 80 100 km

-25°

25°-

26°-

24°-

WESTERNBUSHVELD COMPLEX

MOKOPANE

MIDDELBURG

Steelpoort fault

EASTERNBUSHVELD COMPLEX

Wonderkop fault

Kalkloof anticline

Schwerin foldDerdegelid pericline

Steelpoort pericline

BURGERSFORT

30° I

29° I

28° I

27° I

26° I

f

N

f

f

f

f

I

29°

I

28°

I

27°

Lower, Main and Upper Zone

Critical Zone

fFold axisFault

f

I

26°

-24°

I

30°

Brits Graben

f

BELA-BELA

PRETORIA

0 20 40 60 80 100 km

- 25° 25° -

24° -

MOKOPANE

MIDDELBURG

Steelpoort fault

EASTERN BUSHVELD COMPLEX

Wonderkop fault

Kalkloof anticline

Schwerin foldDerdegelid pericline

Steelpoort pericline

BURGERSFORT

30°I

29°I

f

f

f

f

f

I

29°

- 24°

I

30°Lower, Main and Upper Zone

Critical Zone

fFold axisFault

PPL

Lebowa

Modikwa

Two Rivers

Everest South

MarulaMessina

f

BELA-BELA

PRETORIA

0 20 40 60 80 100 km

- 25° 25° -

24° -

MOKOPANE

MIDDELBURG

Steelpoort fault

EASTERN BUSHVELD COMPLEX

Wonderkop fault

Kalkloof anticline

Schwerin foldDerdegelid pericline

Steelpoort pericline

BURGERSFORT

30°I

29°I

f

f

f

f

f

I

29°

- 24°

I

30°Lower, Main and Upper Zone

Critical Zone

fFold axisFault

PPL

M’Phatlele

Phosiri

Ga-Phasha

Mareesburg

Kennedy’s ValeGrootboom

Sheba’s RidgeBlue RidgeRietfontein

Tjate

Everest NorthMapoch The BergKlipriver/Tinderbox

Garatouw/Genorah

Buffelsvlei

Lower, Main and Upper Zone

Critical Zone

fFold axisFault

NORTHERN LIMB

0 20 40 60 80 100 km

MOKOPANE

29°I

28°I

I

29°I

28°

- 24° 24° -Boikgansho

PPL

Oorlogsfontein

Grass Valley

Aurora

Rooipoort

Tweespalk

MokopaneUitloop

24 Rivers

TurfspruitRietfontein

UG2 - Grade

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10D

e W

ildt

Ela

nd

Pan

dora

Mar

ikan

a

Wes

izw

e

WBJV

Rui

ghoe

k

Witk

leifo

ntei

n

Tusc

henk

omst

Roo

dera

nd

M'P

hatle

le

Ga-

Pha

sha

Sm

okey

Hills

Mar

eesb

erg

Gro

otbo

om

Spi

tsko

p

Ken

nedy

's

Eve

rest

Nor

th

Blu

e R

idge

Gra

de (g

/t)

Western Bushveld Eastern Bushveld

UG2 - Prill Split

020406080

100D

e W

ildt

Ela

ndP

ando

raM

arik

ana

Wes

izw

eW

BJV

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ghoe

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itkle

ifont

ein

Tusc

henk

omst

Roo

dera

nd

M'P

hatle

leG

a-P

hash

aS

mok

ey H

illsM

aree

sber

gG

root

boom

Spi

tsko

pK

enne

dy's

Eve

rest

Nor

thB

lue

Rid

ge

Prill

Spl

it (%

)

AuRhPdPt

Western Bushveld Eastern Bushveld

Merensky - Grade

0

1

2

3

4

5

6

7

8M

arik

ana

WBJV

Wes

izw

e

Rui

ghoe

k

Roo

dera

nd

(Nkw

e)

Roo

dera

nd

Witk

leifo

ntei

n

Tusc

henk

omst

M'P

hatle

le

Ga-

Pha

sha

Spits

kop

Ken

nedy

's

Vale

Gro

otbo

om

Gra

de (g

/t)

Eastern BushveldWestern Bushveld

Merensky - Prill Split

0

50

100M

arik

ana

WBJ

V

Wes

izw

e

Rui

ghoe

kR

oode

rand

(Nkw

e)R

oode

rand

Witk

leifo

ntei

n

Tusc

henk

omst

M'P

hatle

le

Ga-

Phas

ha

Spits

kop

Kenn

edy'

sVa

leG

root

boom

Prill

Spl

it (%

) AuRhPdPt

Western Bushveld Eastern Bushveld

Platreef - Grade

012345

Gra

ss V

alle

y

Roo

ipoo

rt

Oor

logs

font

ein

Mok

opan

e

Auro

ra

Rie

tfont

ein

Boik

gant

sho

Moo

ipla

ts

Sheb

a's

Rid

ge

Losk

op

Gra

de (g

/t)

Eastern BushveldNorthern Bushveld

Platreef - Prill Split

020406080

100

Gra

ss V

alle

y

Roo

ipoo

rt

Oor

logs

font

ein

Mok

opan

e

Auro

ra

Rie

tfont

ein

Boik

gant

sho

Moo

ipla

ts

Sheb

a's

Rid

ge

Losk

op

Prill

Spl

it (%

)

AuRhPdPt

Northern Bushveld Eastern Bushveld

Barriers to Juniors

• Access to mineral tenements• Technical knowledge• Process capability and capacity• Funding

Contribution of Juniors to Exploration• Challenge paradigms• Potential of smaller deposits• Audit Trail• Good Practice• Detail audits and reviews• Open to other approaches

Res

ourc

e E

stim

atio

n

Merensky Reef Histograms

FW2

FW1a

FW1b

CrPegmatoidal Feldspathic Pyroxenite

Feldspathic Pyroxenite

Leuconorite

Mottled Anorthosite

Mer

ensk

y re

ef

PGE Concentration

1m

1m

PGE Concentration

Mer

ensk

y re

ef

FW2

FW1a

FW1b

Chromitite

Feldspathic Pyroxenite

Mottled Anorthosite

Leuconorite

1m

1m

0

Mer

ensk

y re

ef

FW2

Feldspathic Pyroxenite

Leuconorite

Pegmatoidal Feldspathic Pyroxenite

PGE Concentration

Cr

1m

1m

UG2 Chromitite Layer

0 cm

100 cm

Pyroxenite

Chromitite

Chromitite

Pegmatoidal Feldspathic Pyroxenite

Olivine bearing Pyroxenite/ Feldspathic Harzburgite

Leader Seams

Main Seam

Grade

Drilling technologies

• Diamond Drilling• HQ• NQ• BQ• TNW

Sampling

Analytical techniques

• 3PGE+Au • 6 PGE+Au • Pt, Pd, Rh, Ru, Os, Or, Au• Cu, Ni, Co• Concentrations ppm or g/t• Concentrations ppb• Detection limits• Turnaround time

• Fire Assay • Fire Assay – ICP• Fire Assay - Aquia Reqia• XRF – fusion and pellet• AA

A lot more attention to the analytical side of things

Quality Control/Quality Assurance

• Quality ControlCheck on

• Quality AssuranceDesign of Programmes

• Blanks• Duplicates• Standards

MintekAMIS

• Referee

Historic Data

• Sampling Methods• QA/QC relied on Laboratory• Use of in house laboratory• Twin/Verification drilling • Density

Audits and Reviews

• 10% of data• Swapped boreholes• Incorrect thickness

Density

• Bulk Density• Specific Gravity• Methodology

Mining Cut – UG2 Chromitite

• Grade concentrated in chromitite• Interstitial pyroxenites - low grade• Footwall mineralised• Grade histogram• Ability to undermine the leaders• Nature of upper and lower contacts

Mining Cut – Merensky Reef

• Grade is not restricted to one lithology• Hangingwall and footwall mineralised• Grade histogram• Nature of upper and lower contacts• Associated mineralisation e.g. Pseudo Reef

1m

1m

0.00 1.00 2.00 3.00 4.00 5.00 6.00

0.10

0.60

1.10

1.60

2.10

Min

ig C

ut4E Grade (g/t)

2.00

m

0.90

m

FACIES COMPARISON OVER 100cm CUTS

0.00

1.00

2.00

3.004.00

5.00

6.00

7.00

8.00

MINING CUT (cm)

PPE

(g/t)

PEGCRFW1FW3FW6FW7

PEG 3.77 4.63 5.25 5.58 5.87 6.09 6.16 6.00 5.08CR 3.22 3.80 4.31 4.68 4.95 5.15 5.25 5.21 4.81FW1 5.43 5.99 6.39 6.64 6.77 6.75 6.61 6.02 4.78FW3 6.73 6.66 6.38 5.99 5.51 4.98 4.29 3.60 2.69FW6 7.23 7.28 7.19 7.01 6.70 6.34 5.83 5.00 3.83FW7 6.29 6.20 5.88 5.39 4.82 4.20 3.51 2.84 2.04

10100 20100 30100 40100 50100 60100 70100 80100 90100

Grade vs Thickness• Concentration g/t• Content cmg/t

0.00

0.50

1.00

1.50

2.00

2.50

3.00

3.50

4.00

4.50

5.00

0.00 0.50 1.00 1.50 2.00 2.50

Composite Thickness (m)

Gra

de (g

/t)

0

500

1000

1500

2000

2500

3000

3500

Pd Rh Au 4E Pt Cu Ni

Data queries• Data Clustering• Outlier Analysis• Estimation of

different lithologies

• Facies

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

910111213141516171819202122

Con

tribu

tion

to m

eta

l (%)

P GE 2090 remo ved (g /t)

4.0

4.1

4.2

4.3

4.4

4.5

4.6

4.7

Mea

n P

GE2

09

0 (

g/t

)

Outliers: Mean v % Cont. Plot(A ll Data)

C ontr ibut io n to m etal ( %) Mean PG E2 090 ( g/ t)

WHY DO GEOLOGISTS TALK ABOUT FACIES?WHY DO GEOLOGISTS TALK ABOUT FACIES?•• Tool to describe variations that we observe in our reefTool to describe variations that we observe in our reef•• Essentially defines a set of attributes that makes particular reEssentially defines a set of attributes that makes particular reef ef

types unique w.r.t. grade, appearances,types unique w.r.t. grade, appearances,……•• Assists us to understand the nature of the ore bodyAssists us to understand the nature of the ore body•• Better evaluation and hence more accurate planningBetter evaluation and hence more accurate planning•• Optimise extraction of the ore bodyOptimise extraction of the ore body

Benefits of facies determination and delineation

• Identify potential grade distributions within the facies• Investigate the variability of the Merensky Reef• Improve the geostatistics• Improve the evaluation• Improve the in-situ grades inputted into the mine plans• Improve the shafts Head Grade

MERENSKY FACIES CLASSIFICATIONS

PGE Concentration

1m

1mFW2 FW2

FW1a

FW1a

FW1b FW1b

CRCR CR

Pegmatoidal Facies Contact Facies

PGE Concentration

1m

1m

Normal Split Reef WideU

G2

Cyc

le

UG

2 C

ycle

Upper Chromitite Upper Chromitite

Lower Chromitite

Middling

Footwall

Variation across project/mine - Eland Platinum Mine

Normal facies

Split Reef facies

Zilkaatsnek facies

N

Variation across project/mine - Eland Platinum Mine

Geological Losses vs Mining losses• No Reef present • Reef Undeveloped• Not a realistic chance of extraction e.g. base of a

pothole– Potholes– Dykes– Faults– Mafic Pegmatites– IRUPS

Estimation Techniques

• Seam Method• Correlation of sampling • Samples• Ordinary Kriging • Lognormal Kriging• Inverse Distance Squared

Classification

• Known Geology• Good Structure• Facies • Individual Metals

The application of good geological practice is required to obtain the best possible – most accurate – closest to the real value, estimate.

Res

ourc

e E

stim

atio

n

Mineral Resource and Reserve aspects of the Junior Miners on the Bushveld ComplexKen Lomberg