Sigma Lithium Corporation (TSX-V: SGMA) (OTCQB: SGMLF) is pleased to announce the positive results of the independent Feasibility Study prepared for the Xuxa deposit with the initial development of a 1.5 million tonnes per annum open-pit mine and lithium concentrator at Sigma’s 100% owned Grota do Cirilo Project located in the Vale do Jequitinhonha, State of Minas Gerais, Brazil.
Feasibility Study Highlights
Summary of Key Xuxa Feasibility Study Outcomes
The FS for the Xuxa Mine and Xuxa Plant envisages a 1.5 Mtpa spodumene ore mining and lithium concentrate processing operation. Building the Xuxa Mine and Xuxa Plant constitutes a low-risk execution strategy for the Company. The economics are highlighted by high operating margins generated over an estimated 9.2 years of mine life: life-of-mine net revenue of US$ 1.4 billion and LOM EBITDA of US$ 690 million.
The FS is only based only on the current open-pit mining plan without contemplating an underground mine plan.
The FS is based on a 2021 arms-length nominal price forecast of US$ 650 CIF China, and a LOM average price of US$ 733 CIF China or US$629 free on board Brazil for 6% lithium concentrate. Sigma contracted Roskill to provide an outlook and overview of the lithium market. Roskill provided a comprehensive updated market study in August 2019 analyzing current and future trends in the market, prices of lithium chemicals such as lithium hydroxide, lithium carbonate, as well as prices of 6% lithium concentrate for vertically integrated and non-integrated chemical producers.
Table 1 summarizes the financial results from the FS.
Table 1. Financial Results Summary of Feasibility Study for the Xuxa Mine and Plant
|Net present value (NPV 8%) After-Tax||US$||249 million|
|Internal rate of return (IRR) After-Tax||%||43.2%|
|After-Tax Payback period||years||3.1|
|Life of Mine (LOM)||years||9.2|
|Net Revenue during LOM||US$||1.4 billion|
|EBITDA during LOM||US$||690 million|
|Initial Capital Expenditure (Capex) (1)||US$||98.5 million|
|Exchange rate BRL/US$ (2)||BRL/US$||3.85|
|Cash costs per tonne of lithium concentrate (3)||US$/t||238|
|Freight costs to China (3)||US$/t||104|
|Total Cash Cost (CIF China)||US$/t||342|
|Market Prices Roskill Forecast in FS|
|Lithium concentrate CIF China port in 2021||US$/t||650|
|Lithium concentrate CIF China port average LOM||US$/t||733|
|Lithium concentrate FOB Brazil port average LOM||US$/t||629|
Background of Sigma’s Project Development Strategy
Table 2. Xuxa Mining and Concentrate Plant Forecasts at 1.5 Mtpa
Total ore quantity milled (LOM)
Annual run of mine (ROM) ore milled
Spodumene ore feed grade LOM average
|Concentrate Produced LOM Average
Lithium concentrate produced
Lithium recovery rate
Lithium concentrate grade
Lithium carbonate equivalent (LCE) produced
% of Li2O
Tonnes of LCE
|Run of Mine Costs
Mining costs per waste and ore mined
Processing costs per tonne (ROM)
Sigma Lithium Resources CEO Calvyn Gardner says: “This successful Feasibility Study demonstrates that Sigma’s strategy to select Xuxa as the first deposit to be developed in the Grota do Cirilo Project has proven to be the right approach. Xuxa’s low-capital intensity creates the financial robustness to support the economics of a standalone Project. The FS shows that Xuxa has one of the lowest production costs of battery grade lithium concentrate globally, which is also a significant commercial competitive advantage, as it ensures the project is profitable even in the current challenging lithium market environment. The high-quality, coarseness and low impurities of Xuxa’s unique battery grade lithium concentrate has the potential to transform Sigma into a leading supplier to the largest global customers in the electric vehicles and battery supply chain. I am very enthusiastic about the results of this feasibility study, as it shows that Xuxa can unlock the door to develop the entire Grota do Cirilo Project and will pave the way for project bank financing.”
“The Grota do Cirilo Project development strategy is to also bring Barreiro into production potentially using the same Xuxa Plant. Barreiro is a large-sized, high-grade, with a low strip ratio,” adds Mr. Gardner.
Sigma Lithium Resources Chief Strategy Officer Ana Cabral says: “Sigma recognizes and appreciates the collaboration of the new federal and state governments of Brazil and Minas Gerais, who are lending widespread institutional support for the significant advancement of the Project. The specialty coarse high-grade, low impurities and low-cost lithium concentrate of the Xuxa deposit has the potential to position Brazil as a leading “green lithium” supplier to the electric vehicles’ industry globally. Sigma will use green, environmentally clean energy, powering the Xuxa Mine and Xuxa Plant from a hydroelectric plant and Brazil’s green electricity grid. Financially, Sigma’s proposed plant construction pre-payment agreement with Mitsui, could significantly lower the initial equity capital required and thus, has continued to generate wide-spread interest including memoranda of understanding (MOUs) for low-cost project financing from the commercial banks. Results of the Feasibility Study clearly indicate that the Project offers lowered execution risk by bringing together high-grade low-cost Mineral Reserves at Xuxa with existing infrastructure which includes power, roads, and office building, to create a low-risk brownfield project that is expected to deliver significant value to shareholders and local communities.” adds Ms. Cabral.
Independent Consultants Preparing the Feasibility Study
Sigma’s Feasibility Study has been completed to the highest standard. The following international consultants were commissioned to prepare the study:
Mining & Mineral Reserves
Sigma commissioned MCB (Deswick Brazil) to complete the mine plan portion of the FS. The proposed mining operations include a conventional open-pit using hydraulic excavators and a fleet of haul trucks. The FS considers contract mining. Two separate pits will be developed, and four waste piles, which will co-store waste rock from the open pits and Xuxa Plant residue will be constructed.
Key parameters used as part of the pit optimization process include (but are not limited to):
Excavated material will be loaded to trucks and hauled to either the ROM pad or the waste piles. Ore excavation and haulage will be monitored by quality-control personnel and details of material movement will be recorded by a radio dispatch system. Weathered material is considered to be free dig with transitional material to be lightly blasted to loosen it for digging. Fresh rock will be typically blasted on 6m benches for ore domain and 12m benches for waste domain. In order to reduce dilution and maximize mine recovery, controlled blasting (pre-splitting) will be used.
The engineered pit designs include the practical geometry that is required for an operational mine such as the haul road to access all the benches, recommended pit slopes with geotechnical berms, proper benching configuration and smoothed pit walls.
Table 3 summarizes the Proven and Probable Mineral Reserves for the Xuxa deposit.
Table 3. Xuxa Mine Open-Pit Mineral Reserve table:
|Mineral Reserve||ROM (Mt)||Li₂O (%)|
Figure 1 shows the anticipated general site layout plan resulting from the FS.
Figure 1 is available at
Xuxa Plant and Facilities
A three-stage metallurgical test work program was completed by SGS Lakefield.
The Xuxa Plant will be located approximately 1.7 km and 2.3km from the north and south Xuxa mine open-pits, respectively. The DMS plant will use proven and well-established technology, and is designed to produce 220,000 tonnes per annum of minimum 6.0% Li₂O concentrate with an iron content of below 1% Fe₂O₃. The lithium concentrate particle size is anticipated to be between +0.5mm to 9.5mm. Figure 2 shows the planned layout for the in-house crushing system and DMS plant.
Figure 2 is available at
The plant throughput capacity is based on 1.5 Mtpa (dry) of ore fed to the crushing circuit. The current Xuxa Plant design also contemplates a modular and integrated expansion option, with the installation of an in-house crushing circuit to potentially increase processing capacity to 3.0 Mtpa.
The Xuxa Plant will include the following:
The simplified process flow diagram for the proposed Xuxa Plant design is provided in Figure 3.
Figure 3 is available at
The positive FS economics demonstrate that Xuxa is a financially positive standalone project. The key factors influencing the study outcome include the mine average high grade of 1.46% Li₂O and the low levels of impurities leading to high levels of process recoveries with a DMS plant. These in turn lead to low capital expenditures and low ongoing operating costs.
The initial FS capital cost estimate to construct a new 1.5 Mtpa plant and infrastructure, including all direct and indirect costs and 10% contingencies, is estimated at US$98.4 million (with an accuracy of +/- 15%). Costs are summarized in Table 4.
Table 4. Initial Capital Cost Estimate
|Capex Item||Initial Capex
|Processing Plant||$33.2||DMS, Ultrafines DMS, Tails and Concentrate Handing|
|Site Infrastructure||$32.8||Earthworks, Infrastructure, Water & Sewage, Buildings|
|Owner’s Costs & Spares||$5.1||Labor, Admin, Environmental Fees|
|Mining Pre-Production Cost||$13.3||Pre-Stripping (Blasting, Drilling, Haulage, Loading)|
|Plant Pre-Production Costs||$3.0||Mob/Demob, Process Plant Labor, Pre-Production Admin|
|Pre-Production Working Capital||$11.0||Mining and Processing Costs from Commission to Cashflow|
|Initial Capital Cost||$98.4||Funded via Creditors and Offtake Agreements|
Note: Additional non financeable deferred capex and plant and mine closure costs are estimated at US$ 15.2 million to be disbursed by year 9, is detailed as follows: (i) Deferred capex of US$ 5.8 million includes Pit 2 Haul Roads, Balance Pile 1 Excavation, Bridge Between Pit 1 and Pit 2, Waste Piles 3 and 4 Excavation (Clear & Grub, Excavation, Ponds Cuts); (ii) Closure costs for plant and mine closure of US$ 8 million; (iii) Capex of US$ 1.5 million to execute various operational recommendations to be implemented in production.
Operating cost estimates are based on an owner-operated model and have an accuracy of +/- 15%. The operating cost for the mining was provided by MCB. The crushing contracting, substation rental, mobile equipment rental and product transport operating costs were incorporated in the overall operating cost.
The cash operating costs were developed based on third party contract mining and outsourced crushing, as well as on the Xuxa Plant processing cost. The Xuxa Plant is forecasted to have very low operating costs at US$238 per tonne of concentrate as a result of its high grade, high DMS recoveries, low levels of impurities, low cost of electricity and general low country costs.
Table 5 shows the anticipated average operating costs over the LOM. Table 6 presents the forecast revenue and costs on both a total and average LOM basis.
Table 5. Operating Cost Estimate
|Cost Category||LOM Average
US$ / t
|Transportation (CIF China)||$104|
|Selling, General and Administrative||$13|
|Total Cash Cost (CIF China)||$342|
Table 6. Xuxa Estimated Revenue and Operating Costs for 1.5 Mtpa Production
US$ / t
|Less: Realization Costs
Mitsui Prepay Repayment (50,000t)
Freight & Insurance & Storage
Total Realization Costs
|Net Sales Revenue Less Freight & Storage||$1,171||$579|
|Less: Site Operating Costs
Selling, General & Administration
Total Site Operating Costs
|Net Operating Margin
% Net Operating Margin of Net Sales
The FS includes sensitivity analysis of Project NPV 8% using variable CIF China price, recovery rate, ore grade, exchange rate, initial capex, discount rate, operating expenses.
Table 7 shows the impact of a +/- 20% variation of these key factors. Table 8 presents the after-tax NPV results of each factor variance.
Table 7. After-Tax Net Present Value Sensitivity Assumptions for Each Scenario +20% and -20%
|CIF Spodumene Price LOM Avg||[US$ / t]||586||660||733||806||879|
|CIF Spodumene Price 2021||[US$ / t]||520||585||650||715||780|
|Total Opex||[US$ M]||(532)||(599)||(665)||(732)||(798)|
|Total Capex||[US$ M]||(91)||(102)||(114)||(125)||(136)|
|Exchange Rate BRL / US$||[BRL/US$]||3.28||3.69||4.10||4.51||4.92|
Note: A conservative two-tier exchange rate was used as a base to the feasibility study. BRL 3.85 / USD 1.00 for quotes provided from third party information providers and BRL 4.10 / USD 1.00 for the amounts provided in dollars from Sigma.
Table 8. After-Tax Net Present Value Results for Each Scenario
|After Tax NPV (US$ M)||Unit||-20%||-10%||Base||+10%||+20%|
|CIF Spodumene Price LOM Avg||[US$ M]||102||175||249||322||395|
|Recovery Rate||[US$ M]||123||186||249||311||374|
|Total Opex||[US$ M]||335||292||249||205||161|
|Discount Rate||[US$ M]||283||265||249||233||218|
|Total Capex||[US$ M]||266||257||249||240||231|
|Ore Grade||[US$ M]||233||241||249||256||264|
|Exchange Rate BRL / US$||[US$ M]||235||243||249||253||257|
Note: All NPVs calculated using all-in Initial, Sustaining and Deferred Capex of US$ 113.6 M, which adds to initial capex the non-financeable deferred capex of US$ 15.2 million.
The positive economics of the economic feasibility of the Project is further demonstrated in Table 9 by the IRR yield of the combined sensitivity analysis of the after-tax NPV to both 6% lithium spodumene concentrate CIF China prices and discount rate.
Table 9. Combined Sensitivity of Xuxa NPV to Prices and Discount Rate
|Spodumene Price CIF
US$ / t
NOTE: All NPVs Calculated using all-in Initial, Sustaining and Deferred Capex of US$ 113.6 M, which adds to initial Capex the non-financeable deferred capex of US$15.2 million.
Commercial and Marketing Strategy and Offtake Agreements
As a result of the high quality and low impurities of its planned lithium concentrate Sigma has experienced significant commercial success in negotiating offtake agreements with various customers in the electric vehicle supply chain.
Sigma entered the offtake negotiations undertaking a long-term view for the growth of the market and decided to replicate the longer term (five years) contract structures practiced by the lithium chemicals with their cathode industry and other customers in the supply chain. Sigma negotiated offtake agreements with fixed volumes with a multi-year duration, without a price floor, using CIF China market prices as an annual pricing mechanism. By not requesting a price floor, Sigma managed to preserve potential price upside in its offtake agreements, as these agreements do not include a price cap, fixed prices or prices pegged to cost structures of customers in the lithium chemical industry. The offtakes are indexed to Roskill’s published “arm’s length market price CIF China” for spodumene concentrate.
Sigma secured non-binding MOUs to supply 100% of its projected production of 220,000 tpa from Xuxa Plant for a five-year period, commencing in 2021.
Sigma has entered into a binding heads of agreement (the Agreement) for an offtake, funding and strategic partnership with Mitsui & Co., Ltd. of Japan (Mitsui) for a significant portion of the funding required for the capital expenditures and construction of the Xuxa Mine.
Pursuant to the Agreement, Mitsui and Sigma have agreed terms on:
Sigma is currently in negotiations with the other potential off-take customers to sign binding heads of agreement for the 160,000 tpa balance of its annual production.
Lithium Price Forecast and Lithium Chemical Supply Dynamics
Sigma contracted Roskill to provide an outlook and overview of the lithium market.
Roskill provided price forecasts through to 2032 for spodumene concentrate prices for the three categories of 6% spodumene lithium concentrate pricing structures, as described below. This distinction is critical, as the world’s largest spodumene concentrate producer Talison Lithium in Australia practices inter-company pricing (as that company is 51% owned by Tianqui and 49% owned by Albermarle). The three-tier pricing forecast published by Roskill is based on the tracking of following shipments:
Prices for all contracts peaked in 2018, within a range of US$560-1,050 / tonne reflecting Talison to Tianqi/Albemarle inter-company shipments at the lower end and Galaxy to third party customers at arm’s length at the high end.
Related-party contracts fell in the middle of these two end-members and remain the benchmark average to 2032. Related-party contracts are expected to fall to US$600/t by 2021 before steadily increasing into the late-2020s.
Arms-length sales are expected to show a premium to related-party sales of around US$100/t, with inter-company contracts at a US$100/t discount. However, if lithium carbonate and hydroxide prices increase at a greater rate going forward, the chemical-grade spodumene price could increase towards the high case scenario, and vice versa.
Spodumene concentrate pricing inputs for the FS as provided by Roskill in August 2019 are illustrated in Figure 4.
Figure 4 is available at
Demand for lithium rose by 20% in 2018 to reach over 261,100t LCE. The rechargeable battery market, led by the automotive sector increased its consumption of lithium by 30,000t LCE in 2018, representing 93% of the overall increase in lithium consumption.
The short-, medium- and long-term lithium demand outlook appear strong. Consumption of lithium will continue to be driven by the rechargeable battery sector, which is forecast to register 19.9%pa growth through to 2033, reaching around 1.8Mt LCE in Roskill’s base-case scenario. The automotive and energy storage system applications are expected to underpin both battery and overall lithium consumption growth
As a result of the electric vehicle battery demand becoming the main growth driver for lithium chemical demand, the dominance of brine operations in global lithium production has been gradually falling.
As the electric vehicle original equipment manufacturers (OEMs) demand more energy efficient batteries with increased range, the cathode industry increasingly migrates to using lithium hydroxide as the preferred chemical raw material, instead of lithium carbonate. Lithium carbonate is the main product produced and consumed in the lithium market, although lithium hydroxide use is growing at a faster rate. Battery-grade lithium carbonate accounted for around 70% of carbonate use in 2018.
Feedback from our potential customers indicate that the conversion of 6% battery grade spodumene concentrate to lithium hydroxide is the most efficient method of producing it. Moreover, spodumene concentrate with low impurities is less expensive to process (‘clean’) into hydroxide chemicals, increasing operational efficiencies at the chemical producer, thus becoming a competitive advantage.
Battery grade lithium carbonate produced from brine must be converted into lithium hydroxide for use in the cathode industry. Feedback from our potential customers indicate that such conversion has a similar cost to converting to lithium hydroxide the 6% lithium concentrate produced from hard rock ore. Therefore, brine producers of lithium carbonate have been increasingly stripped of a relative competitive advantage over hard rock producers of lithium.
Sigma’s commercial success competing against brines can be examined in the current bear market and current downturn in lithium prices. The lowest “arm’s length’ selling price for competing lithium carbonate raw material from brines to be used by a lithium hydroxide plant is assumed to be the technical grade carbonate from domestic Chinese market, currently priced at $5500/tonne to $6000/ tonne. In order to be competitive with these prices, a hard rock producer needs to have the ability to profitably supply 6% spodumene lithium concentrate at a maximum range of $680 – $750 / tonne, the equivalent of $6000 / 8 (it takes 8 parts of spodumene concentrate to produce one part of hydroxide chemical). These price levels are compatible with Sigma’s cost curve and profitability as demonstrated in the FS.
Figure 5 shows the lithium consumption actuals and forecasts for the period 2014 to 2033.
Figure 5 is available at
In compliance with CONAMA Resolution 09/90, the environmental licensing of mining projects is always subject to the following study progression. The first stage is an Environmental Impact Study (EIS), which is followed by an Environmental Impact Report (EIR), which supports the technical and environmental feasibility stage of the project and the granting of a Preliminary License (Licença Previa or LP) and/or a concurrent Preliminary Licence with an Installation License (Licença de Instalação or LI), collectively referred to as the (LP+LI).
The licensing process in Minas Gerais was developed in accordance with COPAM Regulatory Deliberation N° 217, dated December 6, 2017, which sets out the criteria that must be addressed based on the size of a planned mine, and its likelihood of generating environmental damage. Sigma has successfully obtained an environmental license for open-pit mining activities in respect of metallic minerals except iron ore, with the following parameters:
A water usage license for the project of 150 m3 per hour has already been granted.
Recommendations and Execution
The next phase is for Sigma to commence the detailed engineering work. The first phase of the detailed engineering will take 4 months after which plant construction can commence. Construction is planned for March 2020 and a 12 to 14-month program is envisaged to build the facility and to commission.
About Sigma Lithium Corp.
Sigma Lithium Corporation is a Canadian mining company focused on advancing its principal lithium deposits at its Grota do Cirilo Project in Brazil. Sigma commissioned its pilot plant and has commenced the production of battery-grade spodumene concentrate from its high-quality deposits. Sigma’s corporate mission is to execute its strategy while embracing environmental, social, safety and governance principles. The company is on track to become an ultra-high-quality lithium concentrate supplier to the electrical vehicle and energy storage battery industry worldwide.
Sigma shareholders include some of the largest ESG- (environmental, sustainability, governance) focused institutional investors in the world. Sigma plans to start construction of a commercial-scale lithium concentration plant in 2020, becoming a fully operational sustainable lithium producer in 2021. Sigma, through its subsidiaries, has 27 mineral rights in four properties spread over 191 km2 which includes nine historical lithium mines. The Grota do Cirilo property, Sigma’s primary focus, includes 10 mining concessions (mining production authorizations).
Sigma has a NI 43-101 technical report on the Grota do Cirilo property prepared by SGS, which includes estimated Measured and Indicated Mineral Resource of approximately 46 million tonnes at an average grade of 1.42% Li2O. The technical report also includes estimated Inferred Resources of 6.64 million tonnes at an average grade of 1.46% Li2O and further notes the potential for significant resource expansion.
The technical and scientific information in this press release has been reviewed and approved by Marc Antoine Laporte, P.Geo., M. Sc., of SGS Canada Inc. Mr. Laporte is a Qualified Person as defined by National Instrument 43-101 and is independent of Sigma.
The technical and scientific information in this press release has been reviewed and approved by Ara Erzingatzian, P.Eng, of Primero Group Americas Inc. Mr. Erzingatzian is a Qualified Person as defined by National Instrument 43-101 and is independent of Sigma.
The technical and scientific information in this press release has been reviewed and approved by Porfirio Cabaleiro Rodriguez, Mining Engineer of GE21 Consultoria Mineral Brazil. Mr. Rodriguez is a Qualified Person as defined by National Instrument 43-101 and is independent of Sigma.
The FS source document for the information presented in this press release has been reviewed and approved by the following Qualified Persons as defined by National Instrument 43-101 and who are independent of Sigma:
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We acknowledge the [financial] support of the Government of Canada.