Sayona’s Authier Lithium Project in Québec, Canada is a hard rock spodumene lithium deposit set to play a key role in the Company’s planned multi-project Abitibi lithium hub, as a source of supplementary ore for processing at NAL when production restarts.
Following the acquisition of the NAL mine and concentrator in August 2021, the Authier project’s operating strategy was revised to include only mining operations and waste and water management on-site.
The project is set to become a supplier of ore to Sayona’s nearby North American Lithium operation , which has an established concentrator, thereby minimising the need for mining infrastructure and related environmental impacts at Authier.
Sayona Mining acquired 100% of the Authier project in July 2016. The project’s key attractions include its near-term development potential, access to world-class infrastructure and labour, economical hydroelectric power and its strategic location near North American battery markets.
The Authier project is situated 45 kilometres northwest of the city of Val d’Or, a major mining service centre in Québec. Val d’Or is located approximately 466 kilometres north-east of Montreal. The project is easily accessed by a rural road network connecting to a national highway a few kilometres east of the project site.
The project area comprises 19 mineral claims totalling 653 hectares, and extends 3.4 kilometres in an east-west, and 3.1 kilometres in a north-south direction, respectively. The mineral claims are located over Crown Lands.
The deposit is hosted in a spodumene-bearing pegmatite intrusion. The deposit is 825 metres long, striking east-west, with an average thickness of 25 metres, minimum 4 metres and maximum 55 metres, dipping at 40 degrees to the north. The current pit optimisation has the mineralisation extending down to 200 metres depth but the deposit remains open in all directions.
(Above) Isometric views of the Authier pit with the mineralised envelope on the left from the February 2017 PFS
In November 2019, Sayona completed a revised Definitive Feasibility Study confirming the project’s viability as a profitable and sustainable new lithium mine that will provide new jobs, investment and strong returns for all stakeholders.
In April 2023, Sayona announced a Definitive Feasibility Study for the production of spodumene (lithium) concentrate production, combining its North American Lithium operation with the Authier project.
The Authier project will consist of an open‐pit mine operated by a mining contractor, a waste and overburden stockpile, site water management infrastructures, a mine garage including a wash bay, administrative trailer‐type buildings, a 600 kV electrical distribution system and an ore stockpile area. The run‐of‐mine (ROM) ore will be transferred to highway trucks and transported to the NAL site, where it will be blended (33% Authier/ 67% NAL) with the NAL ore material and fed to the primary crusher (equivalent to a blend of 36% Authier / 64% NAL at the rod mill).
The mining operation will comprise a conventional surface mining method with drill rigs, excavators and off‐highway trucks. The April DFS resized the open pit and infrastructure for a 22‐year life‐of‐mine (LOM) plan to feed the NAL crusher at a rate of approximately 530,000 tonnes per year.
1. The Mineral Resource estimate has been estimated in accordance with the JORC Code (2012)
2. Mineral Resources that are not mineral reserves do not have demonstrated economic viability. There is no certainty that all or any part of the Mineral Resources estimated will be converted into Mining Reserves.
3. Bulk density of 2.71 t/m3 is used.
4. Effective date 6 October 2021.
5. Only Blocks centroids had to be inside the pit to be considered.
6. Pit used: Authier20210821_977.dxf
7. Rounded to the nearest thousand. Rounding may result in apparent summation differences between tonnes, grade, and contained metal content.
8. This estimate of Mineral Resources may be materially affected by environmental, permitting, legal, title, taxation, socio‐political, marketing, or other relevant issues.
9. Open pit Mineral Resource statement is reported at a cut‐off grade of 0.55 % Li2O
10. Cut‐off based on a spodumene concentrate prices of US$977/tonne for a 6% Li2O concentrate
11. Exchange rate of 1.32 CAD / USD
12. Drillhole composites average 1.5m in length.
14. The retained grade interpolation for the Authier lithium Mineral Resource block model is the inverse distance square (ID2) methodology.
15. Revised pit optimisation parameters were provided by BBA to generate the pit shell.
1. Ore Reserves are measured as dry tonnes at the crusher above a diluted cut‐off grade of 0.55% Li2O.
2. Ore Reserves are based on an ore selling price of C$120/t, delivered to the NAL crusher. The ore selling price has been settled in a memorandum of understanding between Authier and NAL.
3. The reference point of the Ore Reserves is the NAL crusher.
4. In‐situ Mineral Resources are converted to Ore Reserves based on pit optimisation, pit design, mine scheduling and the application of modifying factors, all of which support a positive LOM cash flow model. According to JORC code, inferred resources cannot be converted to Ore Reserves.
5. The waste and overburden to ore ratio (strip ratio) is 6.1:1.
6. The Ore Reserves for the Authier Lithium Project have been estimated by Ms. Isabelle Leblanc, P.Eng., OIQ #144395, a Competent Person as defined by JORC.
7. Ore Reserves are valid as of 27 March 2023.
8. Totals may not add up due to rounding for significant figures.
For the conversion of Mineral Resources to Ore Reserves, it is necessary to apply a variety of modifying factors:
1. Metallurgical Recoveries: A mass balance was produced based on the NAL restart flowsheet, feeding a blended ore consisting of 33% Authier ore and 67% NAL ore. Lithium recovery over the LOM is estimated to be an average of 67.4% for the blend based on metallurgical test work results and historical operational data.
2. Cut‐off Grade: A metallurgical cut‐off grade (COG) of 0.55% Li2O was used.
3. Mining Dilution and Mining Ore Losses: A detailed dilution model was developed by BBA Inc. and coded into the mining block model. The mining ore losses are approximately 2.3% and the mining dilution is approximately 9.0% dilution. To account for operational errors and losses during rehandling of ore, an additional mining ore loss factor of 2% was considered, for a total of 4.3% ore losses.
4. Iron content: The iron content can have an impact on the metallurgical recovery and on the quality of the spodumene concentrate. Inside the pegmatite dyke, iron content is approximately 0.7% to 1.0% Fe while the average iron grade in the host rock is around 7% Fe.
5. Status of Environmental Approvals, Mining Tenements and Approvals and Other Government Factors: In November 2022, Sayona sent a new Project Notice to the Quebec Ministry of the Environment, the Fight against Climate Change, Wildlife and Parks (MELCCFP). In February 2023, MELCCFP notified Sayona that the Authier Lithium Project will be subjected to the BAPE procedure. A revised ESIA will be produced in 2023. Following receipt of the Governmental Decree, Sayona will have to obtain various permits for construction and operation of the mine.