Overview
Stage | Construction |
Mine Type | Open Pit |
Commodities |
|
Mining Method |
|
Processing |
- Filter press plant
- Purification & crystallization
- Desliming
- Reverse osmosis
- Flotation
- Leaching plant / circuit
- Dense media separation
- Magnetic separation
|
Mine Life | 47 years (as of Jan 1, 2018) |
Early mining operations began at Mount Holland in early-2022 (Thiess commenced mobilisation and early mining operations in January 2022), courtesy of Thiess, and full production is expected by the second half of 2024.
Construction of the Covalent Lithium’s Kwinana refinery will commence in 2022 and is expected to be completed in 2024. The refinery will convert lithium concentrate into high-purity lithium hydroxide monohydrate for use in products like lithium batteries to store renewable energy. |
Latest News | Decmil builds lithium sector with Covalent, Talison April 8, 2022 |
Source:
Covalent Lithium Pty Ltd (Covalent) is the manager appointed by a joint venture between subsidiaries of Sociedad Química y Minera de Chile S.A. (SQM) and Wesfarmers Limited to develop and operate the Mount Holland Lithium Project, which will be a unique, fully integrated producer of battery quality lithium hydroxide in Western Australia.
Summary:
The Earl Grey pegmatite is hosted within a series of steeply dipping ultramafic and mafic rocks of Archaean age. The pegmatite consists of a main tabular body of approximately 1,000m in strike length, over 2,000m in dip extent, and thicknesses of up to 100m. This main pegmatite is flanked by several hanging wall and footwall dykes, and the main body itself branches into multiple dykes at its southern and eastern extents. The pegmatite dips 5-15° to the north west and is slightly offset by several north-south trending fault zones.
The mineralogy of the pegmatite consists of a simple albite-quartz-microcline-spodumene-petalite assemblage with minor biotite, muscovite and tourmaline. The only significant mineralogical variation across the deposit occurs within the lithium aluminosilicates; spodumene, petalite and several alteration phases occur in discrete domains.
Spodumene is present in two forms at Earl Grey; a coarse form produced during initial crystallisation of the melt, and a finer spodumene-quartz intergrowth (SQI) derived from the isochemical inversion of petalite.
Summary:
The Mount Holland Lithium Project (the project) is an integrated project consisting of a mine, concentrator, and refinery to produce battery quality lithium hydroxide (LiOH) for the international market.
Conventional open pit mining utilising experienced contractors will be adopted at Earl Grey(subject to further study). The mining method was evaluated for a traditional truck and hydraulic excavator (backhoe) operation, combined with suitable drill and blast. The operation evaluated different bench heights in different areas of the pit. In the pegmatite and waste contact zones, mining was determined to be standard 5m benches (2 x 2.5m flitches), and a 10m bench height was assumed for bulk waste mining outside of these zones. Ramp widths were maintained at a nominal 30m. A series of 15 pit designs (staged cutbacks) are planned with mining developing from the initial pits at the south end where the pegmatite comes to surface and proceeding in a northerly direction as the deposit is systematically mined down dip. Equipment (100t-200t excavators loading 100-200t trucks) has been selected and scheduled to meet the 2Mtpa plant throughput. Overall the pit design contained 94.2 million tonnes of ore at 1.5% Li2O and 421 million tonnes of waste at an overall strip ratio of 4.5 to 1.Dump trucks will haul ore to the ROM pad approximately 2km haul from the pit crest to the ROM. After various pit optimisations were performed using the geological block model which supports the Mineral Resource, along with detailed design and scheduling, cash flow modelling and consideration of sensitivities with revenue factors and metallurgical recovery, the contained inventory of plant feed within the pit designs was considered to meet the requirements of an ore reserve. Stage 1 (Proven) is limited to pit 10 where the waste is contained within the area under application for disturbance. Stage 2 (Probable) extends excavation to pit 15 where the boundary of the pit is defined by the economic limits of the predominantly spodumene mineralisation. (Note that the optimisation of the resource focussed on the spodumene zones only, and excluded the petalite and mixed zones which were assumed to have no economic benefit).
The mine plan focussed on minimising land disturbance, with approximately 25% of the waste rock volume as in-pit backfill.
For the purposes of the study, a dilution factor of 104% and mining recovery of 98% have been used. This reflects the broad, well defined and sharp boundaries of the pegmatite/mafic waste rock contacts and has been determined after undertaking a process of regularising the Mineral Resource model using a wide range of block sizes to establish an effective standard mining unit of 5m x 5m x 2.5m. In practical terms detailed grade control will inform the mine planning & geology team to enable them to use non-horizontal and non-constant thickness flitches to expose mineralised pegmatite and mine the pegmatite cleanly will improve these figures.
Flow Sheet:
Crusher / Mill Type | Model | Size | Power | Quantity |
Jaw crusher
|
|
|
|
1
|
Cone crusher
|
|
|
|
1
|
High Pressure Grinding Rolls (HPGR)
|
|
|
|
1
|
Ball mill
|
|
|
|
2
|
Ball mill
|
|
|
|
1
|
Summary:
The Concentrator will process approximately 2 Mtpa of ore to produce approximately 0.4Mtpa of dry spodumene (5.5 wt% Li2O) over the life of the mine. The Concentrator will operate 24 hours a day, 365 days a year, apart from periods of shut down for maintenance activities.
A two-stage crushing circuit, including a primary and secondary crusher will deliver crushed ore to a coarse ore stockpile.
Tertiary crusher undersize is slurried and pumped to a cyclone. The cyclone underflow feeds a Classifier which classifies at a given size.
The mid-sized DMS material reports to the ball mill feed, while the fines from the Classifier reports to the ball mill discharge hopper. This combined ball mill discharge stream is cycloned with its coarser underflow fraction requiring further grinding being recycled to the ball mill feed. The on-size material is pumped forward to the flotation preparation circuit.
The lithium hydroxide refinery (LHR) will includes two Ball mills, one per each processing train.
Processing
- Filter press plant
- Purification & crystallization
- Desliming
- Reverse osmosis
- Flotation
- Leaching plant / circuit
- Dense media separation
- Magnetic separation
Flow Sheet:
Summary:
Processing facilities will consists of concentrator plant and a two-processing train lithium hydroxide refinery (LHR) located at city of Kwinana. Plant will treat ore from Mt Holland mine at a rate of 2 million tonnes per annum (tpa).
The Concentrator will process approximately 2 Mtpa of ore to produce approximately 0.4Mtpa
of dry spodumene (5.5 wt% Li2O) over the life of the mine. The Concentrator will operate 24
hours a day, 365 days a year, apart from periods of shut down for maintenance activities.
The Concentrator infrastructure to be constructed includes:
- Run of Mine (ROM) Pad;
- ROM bin;
- Crushing plant circuit;
- Classification and Mica removal circuit;
- Dense media separation (DMS) circuit;
- Grinding and desliming circuit;
- Magnetic material removal circuit;
- Flotation circuit;
- Product handling and storage area;
- Reagent storage areas;
- Reverse osmosis (RO) plant (0.073 Gigalitre ........

Projected Production:
Commodity | Units | Avg. Annual |
Lithium
|
dmt
| 50,276 |
All production numbers are expressed as hydroxide.
Operational Metrics:
Metrics | |
Annual processing rate
| ......  |
Annual processing capacity
| ......  |
* According to 2021 study.
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Reserves at December 31, 2018:
Mineral Resources cut-off: 0.5% Li2O
Category | Tonnage | Commodity | Grade |
Proven
|
54.4 Mt
|
Li2O
|
1.5 %
|
Proven
|
54.4 Mt
|
Fe2O3
|
1.3 %
|
Proven
|
54.4 Mt
|
Ta2O5
|
45 ppm
|
Probable
|
39.8 Mt
|
Li2O
|
1.5 %
|
Probable
|
39.8 Mt
|
Fe2O3
|
1.4 %
|
Probable
|
39.8 Mt
|
Ta2O5
|
54 ppm
|
Proven & Probable
|
94.2 Mt
|
Li2O
|
1.5 %
|
Proven & Probable
|
94.2 Mt
|
Fe2O3
|
1.4 %
|
Proven & Probable
|
94.2 Mt
|
Ta2O5
|
50 ppm
|
Commodity Production Costs:
| Commodity | Units | Average |
C1 cash costs
|
Lithium
|
USD
|
...... *†
|
Assumed price
|
Lithium
|
USD
|
...... *
|
* According to 2019 study / presentation.
† Net of By-Product.
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2018 Study Costs and Valuation Metrics :
Metrics | Units | LOM Total |
Total CapEx
|
$M USD
|
......
|
Net revenue (LOM)
|
$M USD
|
......
|
EBITDA (LOM)
|
$M USD
|
......
|
After-tax NPV @ 10%
|
$M USD
|
......
|
After-tax IRR, %
|
$M USD
|
......
|
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Corporate Filings & Presentations:
- Subscription is required.
News:
Aerial view:
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