The Zeus Lithium Project is a planned lithium mine located in Esmeralda County, Nevada, the US. The project is fully owned by Noram Lithium, which has been exploring for lithium rich clays at the property since 2016.
The Preliminary Economic Assessment (PEA) of Zeus Project was published in December 2021. It outlined a $528m cost to develop the lithium project and an after-tax NPV(8%) of $1.3bn and Internal rate of return (IRR) of 31%.
Zeus project has undergone preliminary metallurgical testing, and multiple rounds of surface sampling, and drilling. The Phase VI drill programme was completed in May 2022 and Noram Lithium announced a new round of metallurgical testing on mineralised samples in February 2023.
As of February 2023, the mine plan optimisation is underway to support the completion of a pre-feasibility study of the project.
Location and Site details
The Property is located in Clayton Valley, Esmeralda County in south-west Nevada. The project site lies beside the Clayton Valley Lithium Project around 220 miles southeast of Reno. It can be accessed by either Tonopah or Silver Peak.
Overall, Noram’s property comprises 2,800 acres of claims (placer and lode) on federal land.
In 2016, the company first acquired land in the Clayton Valley. The initial land holding was thereafter trimmed to a core holding of 146 Zeus placer and 136 Zeus II lode claims.
Geology and Mineralisation
The Clayton Valley is a closed type playa surrounded by mountains, and tectonically it occurs in the Basin and Range Province. The province is dominated by horst and graben faulting with sediments deposited are primarily silt, sand, and gravel interbedded with illite, smectite, and kaolinite clays along with volcaniclastics.
Noram focused on exploring the Tertiary Esmeralda Formation featuring fine grained sedimentary and tuffaceous units.
The Zeus deposit forms a part of a section of old lakebed sediments raised above the current Clayton Valley playa by Basin and Range faulting.
The lithium within the sediments is expected to be from the volcanic ash component deposited in the playa lakebed.
Lithium is found in brine, pegmatite and sedimentary deposits. Zeus also has major clay minerals including smectite and illite and non-clay minerals such as calcite, quartz, orthoclase, and chlorite.
Mineral Resource Estimate
Based on the Phase VI drill programme, Noram Lithium announced a significant increase in estimated mineral resources at the Zeus Lithium Project in January 2023.
The Measured and Indicated (M&I) resources at the property increased by 190% compared to the August 2021 Mineral Resource Estimate to 5.17 million tonnes (Mt) lithium carbonate equivalent (LCE) (1,034 Mt at 941 parts per million lithium) at a 400 ppm Li cut-off grade.
Inferred Resources were at 1.09 Mt LCE (235 Mt at 871 ppm Li) at a 400 ppm Li cut-off grade.
Mining
Zeus Mine is expected to involve open-pit mining. An ultimate pit was developed that included most of the property boundary.
The ultimate pit results in more than 190 years of mining activity, assuming a normal daily production of 17,000 tonnes per day (tpd) of mill feed.
The base case scenario would include the first 11 phases, representing first 40 years of mining production.
The company assessed several surface mining methods and a traditional truck and shovel operation is selected as the base case mining method. No blasting or drilling is expected to be required for mining.
It will utilise four 90 tonne class haul trucks, one 12m3 hydraulic excavator and one D8 class dozer as the primary mining production fleet.
Other methods that are considered are Dozer and Scraper, and in-pit breaker and loader methods.
All methods were found to be viable.
Recovery and ore processing
The process plant will have a daily throughput of 17,000 tonnes per day, averaging 1,093ppm lithium.
The expected lithium recovery is 89% delivering 5,971 tonnes of lithium per year.
According to the PEA, the ore will be sized, screened and then transported to the leaching circuit. The lithium will be separated from the clay using sulfuric acid.
Subsequently, the slurry from the leaching circuit will be filtered and the lithium bearing solution will be transported for neutralisation to remove the impurities. The filter cake will be dumped as tailings.
The target mineral is lithium carbonate with 99.5% purity.
Project infrastructure
The infrastructure of the project will include access roads, buildings, yards, sulphuric acid plant with production capacity of 2,500t/d, water supply facilities, waste management and storm water handling facilities among others.
The power will be supplied primarily by the sulfuric acid plant. A connection to the regional power grid will supply secondary power to the project.
It can also source additional power from Cypress, which has a geothermal lease located five miles north of the project.
Key Contractors involved
ABH Engineering prepared the PEA report of the Zeus Lithium Project for Noram Lithium.
Noram Lithium had contracted Native Ads for providing investor relations and associated services, while Arethuse Consultants was selected for the resource estimation and pit design of the project.
For the Zeus lithium deposit, the initial chemical engineering studies on lithium extraction and concentration were conducted at laboratories at the Ghent University, Belgium.
Autec Innovative Extractive Solutions was awarded the contract of providing an independent report on the MDS membrane lithium metallurgical bench test process.
This PEA report includes metallurgical test work conducted by SGS Canada. The testing was conducted at Actlabs in Ontario and AuTec Innovative Extractive Solutions in British Columbia (AuTec).
In February 2023, Noram Lithium contracted Kemetco Research for further metallurgical test work.