ioneer Ltd (ASX:INR) has revealed new drilling results and a maiden ore reserve for its Rhyolite Ridge Lithium-Boron Project in Nevada, US.
A drilling program comprising about 46 holes is being undertaken to upgrade the current lithium-boron resource at Rhyolite Ridge to the measured category and extend high-grade, shallow mineralisation to the south of the proposed starter pit.
Initial assays have been received from the first nine holes showing:
• Higher boron grades (circa 30%) than currently modelled for the area planned to be mined during the first few years; and
• Extension to the south of shallow, high-grade lithium-boron mineralisation.
Assays received to date for the lithium-boron mineralisation
ioneer managing director Bernard Rowe said: “These drilling results extend and further confirm high-grade shallow mineralisation at the Rhyolite Ridge Lithium-Boron Project.
“The strong boron grades within and to the south of the proposed starter pit are likely to provide stronger cash flow in the early years of the project.
Indicative timeline for Rhyolite Ridge
“With the aim of upgrading the current mineral resource and extending the shallow lithium-boron mineralisation further to the south, the three rigs currently on site will continue drilling into 2019.
“This work is a fundamental part of the Rhyolite Ridge definitive feasibility study (DFS), which Fluor Corporation has recently commenced.”
ioneer had released the Rhyolite Ridge pre-feasibility study (PFS) in October 2018.
The PFS included a two-stage mine development – a starter pit covering the first seven years and an expanded pit covering a mine life of over 30 years.
However, the supporting documentation for the ore reserve estimate was only recently finalised. The maiden ore reserve has now been estimated for the first stage of mine development:
• 15.8 million tonnes at 1,900 ppm lithium (equivalent to 1.0% lithium carbonate) and 12,200 ppm boron (equivalent to 7.0% boric acid);
• Containing the equivalent of 160,000 tonnes of lithium carbonate and 1.1 million tonnes of boric acid.
Rowe added: “The recently completed PFS demonstrated the project’s scale, long life and potential to become the lowest cost lithium producer in the world as well as the largest lithium producer in the United States with annual production of 20,200 tonnes of lithium carbonate.”
The highly experienced Fluor (NYSE:FLR) team has commenced work on the DFS which is scheduled for completion in Q3 2019.
The Rhyolite Ridge mineral resources and ore reserves are planned to be updated during 2019 as part of the DFS process.