Australian lithium developer Pilbara Minerals Ltd has reported final results from the recently completed 2017 exploration and resource extension drilling programmes at its 100%-owned Pilgangoora Lithium-Tantalum Project in Western Australia. The results continue to demonstrate the world-class endowment of the Pilgangoora deposit and provide strong support for the ongoing Stage 2 Definitive Feasibility Study (“DFS”).
New zones of high-grade pegmatite mineralisation have been defined across multiple prospects, with thick zones of high-grade mineralisation also intersected outside of the current Mineral Resource at the Central Zone and Monster deposit. Results from the programme will be incorporated into an updated Mineral Resource estimate scheduled for completion in 1Q18.
Additional in-fill RC drilling is scheduled to commence in January 2018.Studies are underway to increase production capacity of the Pilgangoora Project to 5 million tpa, rather than 4 million tpa as originally contemplated, once operations have commenced early next year at the initial targeted production rate of 2 million tpa (approximately 330 000 tpa of spodumene concentrate per annum).
Pilbara Minerals’ Managing Director and CEO, Ken Brinsden, said the results marked the completion of another highly successful exploration field season at Pilgangoora in 2017.
“The resource growth at Pilgangoora in the past three years has been nothing short of remarkable and continues to demonstrate that this is a Tier-1 hard rock lithium-tantalum deposit which is yet to reach its full potential,” he said.
“The exploration and development drilling programmes completed this year are expected to add significantly to the Pilgangoora Mineral Resource over and above the existing 156 million t Resource and 80 million t Ore Reserve which underpin the Stage 1 development. We expect to finalise an updated Mineral Resource in the first quarter of next year which will underpin a new Ore Reserve as part of the Stage 2 DFS due for completion by mid-year.”
“The latest drilling results clearly demonstrate the scaleability of the deposit and provide strong impetus for our plans to lift our Stage 2 production rate to 5 million tpa, equivalent to approximately 800 000 tpa of spodumene concentrate.”
“Given the rapid escalation in customer demand, the robust outlook for the lithium market and continued increases in the Resource and Ore Reserve, we have every reason to believe that Pilgangoora’s production can continue to grow in the future, subject of course to completing the appropriate studies,” added Brinsden.
RC drilling was undertaken over a number of prospects including Far East, Monster, West End and Central. The drilling programme was undertaken by Strike Drilling Pty Ltd using a KWL1000 truck-mounted rig and SDR04 rig mounted on a VD3000 Marooka track base.
The drill holes were designed to test a number of new targets and extensions to the existing resource base. All up a total of 82 holes for an advance of 11 319 m were completed.
Several encouraging new zones of thick near surface pegmatite mineralisation have been identified at West End and Monster North. In addition, high grade thick intercepts have been returned from the north extension of the Central Pit.
Results to date include: 27 m @ 1.68% Li2O from the north extension of Central Pit area and 22 m @ 1.15% Li2O in a new pegmatite sheet at Monster. Drilling results continue to demonstrate significant widths and grades including:
- 27m @ 1.68% Li2O from 258 m and 71pp, Ta2O5
- 25m @ 1.48% Li2O from 92 m and 82ppm Ta2O5
- 20m @ 1.62% Li2O from 141 m and 123ppm Ta2O5
- 12m @ 1.99% Li2O from 184 m and 97ppm Ta2O5
- 22m @ 1.15% Li2O from 10 m and 179ppm Ta2O5
Additional RC exploration drilling is currently being planned for 1Q18 as part of the Stage 2 expansion project with the key objective being to upgrade current Inferred Resources to the Indicated and Measured category. This information, together with the results from the current drilling programme, will form the basis of an expanded Mineral Resource in 1Q18 and an updated Ore Reserve estimation for the Stage 2 expansion project in 2Q18.
Stage 2 Expansion case – Diamond Drilling
A PQ diamond drilling programme has recently commenced at the Central and Eastern prospects. Drill core from this programme will be used for additional metallurgical test work as part of the Stage 2 expansion DFS.
While the company had expected to obtain access to the Mt Francisco Project for exploration drilling during 2017, the process for securing such access to the project area has taken longer than expected.
The company continues to engage in access negotiations with the Kariyarra Native Title Claimant Group and the Mugarinya Community Association, who are the entrusted reserve custodians in the Mt Francisco Project area. The company remains optimistic of obtaining such access rights in the short to near term and looks forward to working collaboratively with the Kariyarra Native Title Claimant Group and the Mugarinya Community Association. A request for Entry Permit has also been lodged with the Aboriginal Lands Trust (ALT), and is expected to be assessed shortly.
Geological studies are currently underway in preparation for the 2018 field programme. Proposed exploration including detailed geological mapping and surface sampling is anticipated to commence in early 2018 following receipt of regulatory approvals and the abovementioned consents. This will be followed up by targeted drilling programmes and resource estimation during the course of the 2018 calendar year.