43% Increase in Mt Carbine Ore Reserves From Western Pit
Released
Released
Announcement PDF
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18th May 2023
43% INCREASE IN MT CARBINE ORE RESERVES
FROM WESTERN PIT EXTENSION
EQ Resources Limited is the 100% owner of the Mt Carbine Tungsten Mine near Cairns.
Highlights:
-
Open cut Ore Reserves tonnage increases from 3.54mt to 5.93mt.
-
43% increase in contained WO3 in open cut Ore Reserves to 1.66m mtu after the 64% increase
in the Mt Carbine Indicated Resource as announced to the ASX on 4 April.
-
Additional Ore Reserves extend the open cut life-of-mine (excl. low-grade stockpile) to a total
of 7 years, with the west and north remaining open for potential further extensions.
-
Only 19% of the In-Situ Mt Carbine Mineral Resources are currently in open cut Ore Reserves
with drilling to continue to bring Inferred to Indicated Resources for further expansion.
EQ Resources Limited ("EQR" or "the Company") is pleased to announce updated Ore Reserves for its Mt
Carbine Tungsten Project (100% ownership) in Far North Queensland.
The Company’s successful 2022 drilling campaigns and corresponding update of the Mt Carbine Mineral
Resource Estimate formed the basis for the significant increase in the estimated open cut Ore Reserves
tonnage and contained WO3 metal. The low-grade stockpile (“LGS”) has been partially depleted since the
previous Ore Reserves update from September 2022.
The Ore Reserves are current as of 15 May 2023 and account for all mining activities undertaken to this date.
Table 1 - Mt Carbine Ore Reserves at 15 May 2023
Reserve Category
ROM Tonnes (mt)
WO3 (%)
Contained WO3 (mtu)
Open Cut - Proven
-
-
-
Open Cut - Probable
5.93
0.28%
1,660,400
Open Cut – Total
5.93
0.28%
1,660,400
LGS - Proven
-
-
-
LGS - Probable
9.77
0.075%
732,750
LGS - Total
9.77
0.075%
732,750
REGISTERED OFFICE: Level 4, 100 Albert Road, South Melbourne, VIC 3205
PRINCIPAL PLACE OF BUSINESS: 6888 Mulligan Highway, Mt Carbine Qld 4871
POSTAL ADDRESS: PO Box 1496, Mareeba Qld 4880
ABN: 77 115 009 106 (ASX: EQR)
T: (07) 4094 3072 | F: (07) 4094 3036 | W: eqresources.com.au
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A comparison to the previous Ore Reserves estimate (as of 01 September 2022) as follows:
•
Open cut ROM tonnes increased from 3.54mt to 5.93mt,
•
Open cut ROM WO3 grade decreased from 0.33% to 0.28%,
•
Open cut contained WO3 increased from 1.161m mtu to 1.660m mtu (1 mtu = 10kg WO3),
•
LGS depleted by 0.23mt,
•
Open cut life-of-mine increased from 4.5 to 7 years.
The increase in the open cut Ore Reserves is predominantly driven by the western extension of the open cut
by 150m. No changes occurred in the centre area of the historical pit as outlined in the December 2022 BFS
Update and as shown in cross section A’-A below.
A’
A
A
A’
Figure 1 - Cross Section through current Resource Model
(Indicated Resources are red, Inferred Resources are green)
Figure 2 - Plan view showing Indicated Resources (in red) and
Inferred Resources (in green)
With the increase in Ore Reserves, the ROM strip ratio within the open cut changed from 3.1:1 (waste t:ore t)
to 3.9:1. The expanded Ore Reserves will be used to update the latest Bankable Feasibility Study (“BFS”)
which is due for completion shortly.
The Ore Reserves have been limited to a practical pit shell based on the current economic limits of the deposit.
The updated mine plan considers the utilisation of larger mining equipment and a reduction in the amount of
costly selective ore mining, which supports a further improvement of the project economics. An isometric view
of the Ore Reserves pit shell is shown in Figure 3.
BFS Pit - Nov 2022
BFS Pit - May 2023
Figure 3 - Isometric View of Ore Reserves Pit Shell
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Ramps were designed into the pit shell using suitable widths and grades to accommodate the planned open
cut mining fleet. The open cut shell and the LGS were subdivided into detailed mining blocks which were then
fully scheduled, including haulage modelling, for the planned life-of-mine. The results of the schedule were
then assessed in a financial model to determine the overall economic viability of the project. Only Ore
Reserves, including the LGS, were used to generate revenue, with all other materials classified as waste.
Concentrate Price Assumptions
Revenue assumptions are based on the forecast for ammonium paratungstate (APT) price starting at
US$340/mtu (metric tonne unit, 1mtu=10kg) in 2023 increasing to US$376/mtu in 2029 with a AUD:USD
exchange rate of 0.67 applied. The final realised price for each tonne of 50% WO3 concentrate used in the
financial model is AU$17,761 in 2023 increasing to AU$19,642 in 2029. This includes a 70% payable rate of
the WO3 in the APT.
For further detailed information, please refer to the Ore Reserve Report published on the EQ Resources
Website: www.eqresources.com.au/site/invest-in-us/technical-reports
Released on authority of the Board by:
Further Enquiries:
Kevin MacNeill
Chief Executive Officer
Peter Taylor
Investor Relations
0412 036 231
peter@nwrcommunications.com.au
About the Company
EQ Resources Limited is an ASX-listed company transforming its world-class tungsten assets at Mt Carbine in North
Queensland; leveraging advanced technology, historical stockpiles and unexploited resource with the aim of being the preeminent tungsten producer in Australia. The Company also holds gold exploration licences in New South Wales. The
Company aims to create shareholder value through the exploration and development of its current portfolio whilst
continuing to evaluate corporate and exploration opportunities within the new economy and critical minerals sector.
Competent Person’s Statements
This Ore Reserves Estimate for the Mt Carbine Project has been prepared by a team of consultants under the guidance of
Mr Tony O’Connell. The Mt Carbine Project consists of (a) the Mt Carbine low-grade stockpile (LGS) and (b) the Mt Carbine
open pit. The estimates of Open Cut Ore Reserves for the Mt Carbine Project as at 15th May 2023 presented in this report
have been prepared in accordance with the requirements of the 2012 edition of the Australasian Code for Reporting of
Mineral Resources and Ore Reserves (2012 JORC Code). Mr O’Connell is a qualified Mining Engineer, (BE (Mining),
University of Queensland), has over 24 years of experience in the global mining industry and is a member of the
Australasian Institute of Mining and Metallurgy (AusIMM). Mr O’Connell has sufficient experience that is relevant to the
style of mineralisation and type of deposit under consideration and the activity being undertaken to qualify as a Competent
Person as defined in the JORC Code. Mr O’Connell consents to the inclusion in the report of the matters based on his
information in the form and context in which it appears. Neither Mr O’Connell or Optimal Mining Solutions Pty Ltd has any
material interest or entitlement, direct or indirect, in the securities of EQ Resources Limited or any associated companies.
Fees for the preparation of this report are on a time and materials basis only. Mr O’Connell consents to the release of the
report, in the form and context in which it appears.
Forward-looking Statements
This announcement may contain forward-looking statements. Forward-looking statements address future events and
conditions and therefore involve inherent risks and uncertainties. Actual results may differ materially from those currently
anticipated in such statements. Particular risks applicable to this announcement include risks associated with planned
production, including the ability of the Company to achieve its targeted production outline due to regulatory, technical or
economic factors. In addition, there are risks associated with estimates of resources, and there is no guarantee that a
resource will have demonstrated economic viability as necessary to be classified as a reserve. There is no guarantee that
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additional exploration work will result in significant increases to resource estimates. Neither the Australian Securities
Exchange nor its Regulation Services Provider (as that term is defined in policies of the Australian Securities Exchange)
accepts responsibility for the adequacy or accuracy of this announcement.
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MATERIAL INFORMATION SUMMARY
The Material Information Summary is provided for the Mt Carbine Open Cut Ore Reserves pursuant to ASX
Listing Rules 5.8 and 5.9 and the Assessment and Reporting Criteria in accordance with JORC Code 2012
requirements.
The Material Information Summary covers the open cut component of the Ore Reserves estimate only. The
LGS has not been included in the Material Information Summary as this stockpile has only seen minor tonnes
removed from the Ore Reserves estimate via depletion over the past 9 months. The Ore Reserve estimate for
the open cut is shown in Table 2.
Table 2 – Mt Carbine Open Cut Ore Reserve Estimate at 1 September 2022
Reserve Category
ROM Tonnes (mt)
WO3 %
Contained W03 (mtu)
Open Pit - Proved
-
-
-
Open Pit - Probable
5.93
0.28%
1,660,400
Open Pit - Total
5.93
0.28%
1,660,400
Material Assumptions for Ore Reserves
The Ore Reserves are based on the geological model used as part of the Mineral Resources Statement
compliant with the 2012 JORC Code prepared by Mr. Tony O’Connell, a full-time employee of Optimal Mining
Solutions Pty Ltd. The Mineral Resources are split into two sections, one for the LGS and one for the open cut
(In Situ), as summarised in Table 3 below.
Table 3 – Mt Carbine Resource Estimate at 15 May 2023
Orebody
Resource
Classification
Tonnes
(Mt)
Grade
(WO3 %)
WO3
(mtu)
Low-Grade Stockpile
Indicated
10.126
0.075
759,450
Indicated
18.06
0.30
5,405,901
Inferred
10.68
0.30
3,217,311
Total
28.74
0.30
8,623,212
Total
38.87
In Situ
All
9,382,662
The current Ore Reserve estimate has converted approximately 33% of the in situ Indicated Resources
(18.06mt) to Probable Reserves (5.93mt).
The Mt Carbine project is located on two leases: ML4867 and ML4919, which are surrounded by four
exploration permits as shown in Figure 4.
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Figure 4 - Mt Carbine Tenements
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Details of both mining leases are shown in Table 4.
Table 4 - Mt Carbine Leases
Item
ML 4867
ML 4919
Permit type
Mining Lease
Mining Lease
Permit status
Granted
Granted
Lodge date
23 December 1971
30 November 1972
Approve date
25 July 1974
22 August 1974
Expiry date
31 July 2041
31 August 2041
MT. CARBINE QUARRIES PTY. LTD.
MT. CARBINE QUARRIES PTY. LTD.
CU, FE, MO, SN, W, MT, Q, SI
CU, PB, SN, W, ZN
Mineral
Mineral
Granted before 1 January 1994
Granted before 1 January 1994
358.5
7.891
MT CARBINE NO 1
NEW DCL
Permit number other
4867
4919
Permit type abbreviation
ML
ML
Previous permit number
ML2523MARE
ML2888MARE
Permit ID
108011
108023
Permit type
Mining Lease
Mining Lease
Permit status
Granted
Granted
Authorised holder name
Mineral
Permit sub-type
Native Title category
Area (ha)
Permit name
As Table 4 demonstrates, both mining leases have recently been approved for additional 19-year terms with
their expiry dates extended to 2041.
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A pit optimisation model was established in the Deswik mine planning software package. The package utilises
pseudoflow algorithms to determine the economic pit limit based on several input parameters, including:
•
Operational parameters such as loss, dilution, recovery,
•
Processing parameters such as recovery, moisture adjustments, grade adjustments, etc.
•
Geotechnical parameters to define the overall pit wall angles,
•
Unit cost rates for all processes,
•
Revenue assumptions.
A summary of the unit cost rates utilised in the pit optimisation model are shown in Table 5.
Table 5 - Unit Cost Rates for Pit Optimisation Model
Cost Item
Units
Unit Cost
Drill & Blast
$/t
$1.26
Waste Mining
$/t
$3.27
Ore Mining
$/t
$3.30
Crushing\Screening
$/feed t
$2.00
Ore Sorting
$/feed t
$1.49
Gravity Plant
$/feed t
$12.45
Rehabilitation
$/total t
$0.26
Contractor Overheads
$/total t
$1.34
State Royalty
% of revenue
2.70%
As mentioned previously, the final realised price for each tonne of 50% WO3 concentrate applied in the pit
optimisation model is AU$17,761 in 2023 increasing to AU$19,642 in 2029.
Current processing of the LGS has provided key data for the modifications, upgrades and optimisation of the
processing infrastructure in preparation for the in-situ ore feed. Ore runs through three key processing stages:
•
Crushing and Screening,
•
X-ray Ore Sorting,
•
Gravity Separation.
The processing flow chart for Mt Carbine ore is shown in Figure 5.
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LGS Ore
Open Cut Ore
Fines -6mm
Crush & Screen
Coarse +6mm
Rejects
Bypass (>2% WO3)
Ore Sorting
Rehandling Circuit
Fines -6mm
Tailings
Gravity Plant
Concentrate
Figure 5 - Processing Flow Chart
The factors applied at the various stages of the overall concentrating process are shown in Error! Reference
source not found. below.
Table 6 - Mt Carbine Processing Assumptions
Factor
Crush & Screen Fines/Coarse Mass Split
Value
36%/64%
Crush & Screen Fines WO3 Upgrade
150%
Ore Sorter Mass Recovery Equation
45.45 * Feed Grade + 0.0455
Ore Sorter Tungsten Recovery
90%
Wet Plant Fines Tungsten Recovery
79.3%
Wet Plant Coarse Tungsten Recovery
90%
Wet Plant Total Tungsten Recovery
82.7%
Total Tungsten Recovery
80.3%
The economic pit limit shells generated by the pit optimisation model were then converted into practical pit
shells and stages as shown in Figure 6 and Figure 7. Each stage was designed to Bankable Feasibility Study
(“BFS”) level of detail using the parameters shown in
.
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Table 7 - Mt Carbine Pit Design Parameters
Item
Units
Value
Final Wall Batter Angle
degs
70
Final Wall Bench Height
m
20
Final Wall Bench Width
m
8
Access Ramp Width
m
20
Access Ramp Maximum Grade
%
10
Internal dig solids were created in Deswik and then imported into a BFS level of detail schedule in the Spry
scheduling package. All LGS dig solids plus the out-of-pit dump solids were created and imported into the
schedule. The Spry scheduling model including all dig scheduling, dumping and haulage modelling which
provided accurate truck hours and numbers as the pit progressed.
Screen captures at the start and end of the Spry schedule are shown in Figure 6 and Table 7 respectively.
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Figure 6 - Start of Schedule
Figure 7 - End of Schedule
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Cut Off Parameters
Ore Reserves for the Mt Carbine Open Cut are reported using a ROM cut-off grade of 0.08% WO3. The cutoff was based on the lowest grade ore that still generated a positive cash flow from the Pit Optimisation
calculations using a WO3 ammonium paratungstate sales price of US$340/mtu and BFS level cost inputs.
Mining Factors and Assumptions
Mt Carbine is a historical open cut mine that had ceased operations in the 1980’s. EQ Resources has recently
refurbished processing facilities and infrastructure with additional processing and infrastructure upgrades
being accounted for in the Ore Reserves estimate and BFS.
A mining method assessment determined that medium sized excavators and accompanying trucks are the
most optimal fleet for restarting the existing open cut.
Benches will be blasted in 10m heights and mined off in 3.5m flitches by a 190t class excavator loading 55t
rigid rear dump trucks. Geotechnical reports and the existing open cut pit walls have guided the overall final
pit wall design parameters for 20m high benches with a 70-degree batter and 8m wide catch benches. Haul
ramps have been designed for the 55t trucks at a maximum gradient of 10% with dual lane ramps being 20m
wide and single lane ramps 14m wide. All material mined is hauled out of the pit with ore trucked to the Run
of Mine (ROM) stockpile or direct fed to the crusher and waste trucked to the out of pit dumps.
Due to the resource model including a lower grade halo around higher grade mineralised veins, a minimum
width of 2m was applied to determine if ore blocks could be recovered. Any blocks that did not pass this
assessment were converted to waste and regarded as losses. Any remaining ore blocks that were adjacent to
a waste block had an edge loss and dilution width of 0.36m applied along the ore/waste boundary.
Infrastructure
As the site is an existing operation all major infrastructure is installed with only minor upgrades required which
have been assessed at a PFS level of detail or better.
Costs
With respect to the processing of the ore, costs have been estimated based on a process contractors build up
for capital whilst operating costs have been developed based on the current processing of the LGS in
conjunction with the BFS upgrade information. A mining contractor tender process has provided the operating
unit cost rates for the mining operations. A full financial model has been developed that estimates all costs
from clearing through to mining and production of the final concentrate.
A Queensland State Government Royalty of 2.7% payable on the ex-mine value, less allowable deductions,
of the WO3 APT has been applied.
Financial Assessment
The financial model for the mining and processing schedule calculated the net present value (“NPV”) of the
operation using a discount rate of 8%. The revenue is based on the Ore Reserves only and no value has been
applied to Inferred Mineral Resources nor quarry rock. The project generated a good net present value figure
with all levels of the planned open cut economical to mine and process.
The competent person is satisfied that the proposed mining activities within the mine plan which underpins the
Ore Reserves estimate are realistic and achievable. The competent person is also satisfied that the Ore
Reserves estimate quantities are economical to mine and process, taking into account all foreseeable
operating costs, capital costs, approvals, etc.
Resource Classification
Classification of the Mineral Resource estimate was interpreted on several criteria, including confidence in the
geological interpretation, the integrity of the data, the spatial continuity of the mineralisation and the quality of
the estimation. An assessment of the historical mining showed increased confidence in the surrounding areas
of the open pit and confirmed by drilling results.
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The classification reflected the author’s confidence in the location, quantity, grade, geological characteristics,
and continuity of the Mineral Resources. The data spacing and distribution are sufficient to establish geological
and grade continuity appropriate for Mineral Resource estimation and classification and the results
appropriately reflect the Competent Person’s view of the deposit.
Based on the criteria outlined above, the 818,453 blocks that were interpolated in the Insitu Mt Carbine model,
were classified as follows: 63% are classified as Indicated and 37% are Inferred Mineral Resources. The
remaining blocks are flagged as Target (non-ore lithologies).
Reserves Classification
The classification of the Mt Carbine Open Cut Ore Reserves reflects the view of the Competent Person and is
in accordance with the JORC Code 2012. Probable Ore Reserves have been derived from Indicated
Resources only. No Proved Ore Reserves have been declared.
Audits and Reviews
This Ore Reserves estimate has been reviewed internally by Optimal Mining Solutions Pty Ltd with no errors
identified.
Discussion of Relative Accuracy/Confidence
The accuracy of the estimates within this Ore Reserves are determined by the order of accuracy associated
with the Mineral Resource model, metallurgical recovery data and long-term unit cost rates. It is the opinion of
the Competent Person that the modifying factors and long-term cost assumptions are reasonable.
It is the opinion of the Competent Person that the Ore Reserves estimate is supported by appropriate design,
scheduling and cost estimation to BFS level of accuracy and as such there is a reasonable expectation of
achieving the reported Ore Reserves commensurate with the Probable classification.
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APPENDIX A: SECTION 4 OF TABLE 1 OF THE JORC CODE (2012)
SECTION 4 ESTIMATION AND REPORTING OF ORE RESERVES
Criteria
Mineral
Resource
estimate for
conversion to
Ore Reserves
Site visits
Study status
JORC Code explanation
Commentary
• Description of the Mineral Resource estimate used as a basis for the
conversion to an Ore Reserve.
• Clear statement as to whether the Mineral Resources are
reported additional to, or inclusive of, the Ore Reserves.
• The Ore Reserves have been based on two separate block models,
one for the low-grade stockpile and the other for the open pit
operation.
• The geological model used to develop the final low-grade stockpile
resource model was generated by Measured Group Pty Ltd in
August 2021 and is titled ‘Mt_Carbine_LGS_20210820.bmf’.
• The geological model used for the open pit operation was
developed by EQR in April 2023.
• The Mineral Resources are inclusive of the Ore Reserves.
• Comment on any site visits undertaken by the Competent Person
and the outcome of those visits.
• If no site visits have been undertaken indicate why this is the
case.
• The competent persons visited site on 6th September 2022 and
was provided access to all areas to see how the LGS stockpile
reclaim works were progressing along with the processing
infrastructure upgrades.
• The type and level of study undertaken to enable Mineral
Resources to be converted to Ore Reserves.
• The Code requires that a study to at least Pre-Feasibility Study
level has been undertaken to convert Mineral Resources to Ore
Reserves. Such studies will have been carried out and will have
determined a mine plan that is technically achievable and
economically viable, and that material Modifying Factors have
been considered.
• Mining studies have been completed to a FS level of detail, with a
detailed mine design cut into three phases and subdivided into
3.5m high benches.
• The designed pit solids were intersected with the latest
geological model and then adjusted for loss and dilution.
• A bench-by-bench schedule was compiled with the in situ, ROM and
product information for each dig solid analysed in a financial model.
• Upgrades to the processing equipment have been completed to a FS
level of detail.
• Key performance parameters such as unit operating costs,
metallurgical parameters, etc. have been based on historical
performance at site where practical or contractor quotes.
14
Criteria
Cut-off
parameters
Mining factors
or
assumptions
JORC Code explanation
Commentary
• The basis of the cut-off grade(s) or quality parameters applied.
• A cut-off grade of 0.075% WO3 has been applied for calculation
of the Reserve within the low-grade stockpile.
• A cut-off grade of 0.05% WO3 has been applied in the open pit
geological model, however after loss and dilution calculations are
completed, the final feed grade to the processing plant is as low as
0.08%.
• A cut-off grade analysis has indicated that these two parameters
are conservative and generate sufficient cash flows.
• The method and assumptions used as reported in the PreFeasibility or Feasibility Study to convert the Mineral Resource to
an Ore Reserve (i.e. either by application of appropriate factors by
optimisation or by preliminary or detailed design).
• The choice, nature and appropriateness of the selected mining
method(s) and other mining parameters including associated
design issues such as pre-strip, access, etc.
• The assumptions made regarding geotechnical parameters (eg pit
slopes, stope sizes, etc), grade control and pre- production drilling.
• The major assumptions made and Mineral Resource model used
for pit and stope optimisation (if appropriate).
• The mining dilution factors used.
• The mining recovery factors used.
• Any minimum mining widths used.
• The manner in which Inferred Mineral Resources are utilised in mining
studies and the sensitivity of the outcome to their inclusion.
• The infrastructure requirements of the selected mining
methods.
• Mining of the low-grade stockpile is currently being undertaken by
a 50t excavator and fleet of 45t articulated dump trucks.
• Front end loaders with, ~6m3 buckets, will be used around the
crushers, screens, ore sorters and for general clean up.
• Mining of the open cut operation will be completed in three phases.
• The open pit will be mined with 1 x 190t class excavator, with a 11m3
bucket and a fleet of 55t rigid rear dump trucks or 45t articulated
trucks. A secondary 50t excavator, fitted with a ~3m3 bucket, will
also be used where required. The fleet will move up to 4.5Mt of
waste and ore annually.
• The open pit operations will be supported by ancillary
equipment including a grader, water cart and dozers.
• A 3m3 bucket on the secondary excavator will allow the excavator
to selectively mine the relatively thin orebodies and keep dilution
quantities to a minimum.
• All waste and ore will be drilled and blasted at a powder factor
of approximately 0.8 kg/bcm of material.
• Due to the vertical nature of the orebodies, grade control will be
paramount. It is proposed to complete grade control via a
combination of mapping, face sampling and grade control drilling,
utilizing mostly angled holes.
• Open-pit ramps have been designed at 10% maximum
gradient at a width of 20m.
• Geotechnical parameters for the majority of the open pit are
15
Criteria
JORC Code explanation
Commentary
•
Metallurgical
factors
or
assumptions
• The metallurgical process proposed and the appropriateness of that
process to the style of mineralisation.
• Whether the metallurgical process is well-tested technology or novel
in nature.
• The nature, amount and representativeness of metallurgical test
work undertaken, the nature of the metallurgical domaining applied
and the corresponding metallurgical recovery factors applied.
• Any assumptions or allowances made for deleterious
elements.
• The existence of any bulk sample or pilot scale test work and the
degree to which such samples are considered representative of the
orebody as a whole.
• For minerals that are defined by a specification, has the ore reserve
estimation been based on the appropriate mineralogy to meet the
specifications?
based on the existing pit’s design which has performed well and
remained relatively unchanged since mining stopped in the 1980s.
The key geotechnical parameters for the open pit wall are:
o Batter height
- 20m
o Batter angle
- 70 degrees
o Berm width
- 8m
Currently, the only known area of geotechnical risk exists on the
southern wall near the south wall fault. A geotechnical analysis of
this wall indicates that the current pit design will require rock bolting
at close intervals to minimise the probability of this wall causing
geotechnical disruptions. Capital and operating cost allowances
have been made in the financial assessment to monitor and treat
this wall as it is exposed in the final wall. The two upper benches in
the south wall, which are located in weathered material, have been
excavated at 50 degrees and 57 degrees as specified by the
geotechnical assessment.
• The low-grade stockpile at Mt Carbine is processed through a
combination of crushers, screens, an ore sorter and wet plant circuits
to generate a concentrate containing approximately 50% WO3.
Existing Infrastructure
• The existing crushing and screening flowsheet consists of two
stages crushing and dry screening circuits to produce two
products:
1. –6mm wet plant feed
2. +6mm, -40mm ore sorter feed
• Run of mine (ROM) ore (-700mm) is reclaimed from the low- grade
waste stockpile and is delivered to the fixed jaw crusher. The jaw
crusher has a closed side setting of -75mm. The jaw crusher
discharge belt transfers primary crushed ore
onto a 900mm wide screen feed conveyor. The screening plant
consists of a mobile fitted with two decks to split the
16
Criteria
JORC Code explanation
Commentary
•
•
•
•
•
•
feed into two streams:
1. Oversize (+40mm) to the cone crusher circuit
2. Undersize (-6mm) to the -6mm stockpile
The secondary cone crusher discharge is fed onto a belt
conveyor and recirculates back to the sizing screen for
separation into product sizes.
The existing ore sorter consists of a single hopper feed point, dry
screen to dress ore before the ore sorter and a single ore sorter. The
ore sorter circuit produces two products:
1. Rejects
2. +6mm, -40mm ore sorter oversize that is crushed by a cone crusher
to -6mm for feed into the processing plant.
Ore is fed into the existing processing plant and onto a wet screen
which separates the -6mm material and the +6mm material. The
+6mm material is sent back to the ore sorter for processing.
The -6mm particles are pumped to a pulse jig where the high density,
tungsten bearing particles are concentrated and pumped to a
secondary wet screen with 0.8mm panels on the screen. The +0.8mm
particles are fed to a rolls crusher and then pumped back to the front
of the screen while the -0.8mm sized material is dewatered and sent
to six shaking tables.
The shaking tables produce a rougher concentrate which is pumped
to a final cleaner table. The tailings from the rougher tables are
pumped back to the screen, to be jigged once more to minimise
losses and increase recovery. The cleaner table produces a final
concentrate whic
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