Aspiring producer Aura Energy (ASX: AEE) says it is on track for year end completion of a definitive feasibility study at its flagship Tiris uranium project in Mauritania.
After an extended haitus due to a weak uranium price, the company reported the study is now in “full progress on a number of fronts” including bulk sampling, metallurgical testwork and development of a final process flowsheet, with a view to full release in early 2019 and first production from Tiris in 2020.
Aura has also commenced discussions for uranium offtake and financing of the estimated US$45 million project construction cost with government agencies and potential partners.
Located in the Sahara Desert, Tiris has a mineral resource of 51.8 million pounds and a production target of 1 million pounds per annum, from a measured and indicated 17 million pounds uranium oxide.
A 2014 scoping study estimated the project’s operating costs to be around US$19.40 per pound.
Bulk sampling and testing
In 2018, Aura completed 11 trenches at a depth of 4m each at the Lazare North and Lazare South resources within the Tiris project to collect representative samples for bulk metallurgical testwork.
The trenches were dug with an excavator, demonstrating the “free-digging nature” of the orebody.
The program aimed to determine the variability of key project process parameters such as uranium recovery and sulphur upgrade factors, as well as provide inputs to define geometallurgical processing domains.
Collection of 88 samples (totalling approximately 5 tonnes of material) was done from trenching rather than drilling to maintain sample integrity, allow for sufficient sample mass to be collected and provide information on mining requirements for the material.
Samples were sent to Aura’s facility at Nouakchott, where Mintek Laboratories will carry out testwork for design of the rotary scrubber and screening beneficiation circuit, while ANSTO Minerals will undertake feasibility study tests for design of leaching, ion exchange and uranium purification circuits.
A $50,000 grant under the Australian Government Innovation Connections initiative will support the testwork program with ANSTO.
Technical investigations during the definitive feasibility stage have indicated the potential for the recovery of vanadium as a byproduct from the Tiris process streams.
Vanadium occurs in Tiris ore at a grade of 330 parts per million vanadium pentoxide and approximately half of it is within the project’s uranium host mineral, carnotite.
Vanadium hosted with carnotite would potentially be leached alongside uranium in the project’s extraction circuit.
Aura executive chairman Peter Reeve said the company would consider the recovery of vanadium to be a valuable byproduct for Aura during vanadium’s current resurgence.
“The value of the Tiris project is driven by low operating and development capital costs, and it would benefit further with vanadium recovery which has been considered technically-achievable,” Mr Reeve said.
Battery metals market
Mr Reeve added the Tiris vanadium initiative is part of Aura’s battery metals development strategy to help broaden its portfolio.
It complements the company’s announcement in May of a near-surface high-grade discovery at its world-class Häggån vanadium project in Sweden of 90 million tonnes at 0.42% vanadium pentoxide at a 4,000ppm cut-off.
Häggån is a large polymetallic deposit containing economically-significant levels of vanadium, nickel, zinc, molybdenum and other battery metals.
Vanadium from Tiris would provide Aura with the opportunity for near-term production of vanadium pentoxide with entry to the vanadium market while Häggån is in development.
At mid-afternoon trade, shares in Aura Energy were steady at $0.018.