Basin East Update

RNS Number : 4687X

Bradda Head Lithium Ltd

30 August 2022

 

30 August 2022

Bradda Head Lithium Ltd.

("Bradda Head", "Bradda", or the "Company")

Follow-up Phase 1 Test work at Basin East Enables Pre-Concentration to 1,900ppm Li and Demonstrates Potential for Reduction in Acid Consumption

Bradda Head Lithium Ltd (AIM: BHL, OTCQB: BHLIF), the North America-focused lithium development group, is pleased to announce positive results from the second stage of its preliminary metallurgical test work programme that it has completed with SGS Canada (SGS) on samples from its 100%-owned Basin East lithium deposit. The Company has a JORC-compliant resource of 305kt Lithium Carbonate Equivalent (LCE), at its Basin License area and has plans this year to grow this resource with follow-up drill plans at Basin North (BN) and Basin East Extension (BEE).

Highlights:

· Test work confirms the ability to upgrade the Basin East Li clay mined grade to 1,900ppm Li by using Cyclone Classification (a standard process used for commercial concentration). The knock-on effect of this upgrade is the opportunity for a reduced process plant footprint and potential reduction in acid consumption. This upgrade factor is significantly better than the previously reported factor (see PR dated 12 January 2022).

· The further 26% upgrade factor (from 1,500ppm Li to 1,900ppm Li) is achieved by rejecting 32% of the unmineralised waste material.   A reduction in these impurities in the PLS (Pregnant Leach Solution) helps reduce acid consumption and therefore processing costs.

· Table One below, reflects the reduction in the acid consuming impurities in the upgraded intermediate product--- with Sodium (Na) reduced by 66%, Aluminium (Al) by 46%, Iron (Fe) by 31%, Iron (Fe) by 31%, and Magnesium (Mg) by 20%  This should positively impact on the economics in the planned PEA (Preliminary Economic Assessment) at the Basin Project - by reducing potential acid consumption by c.25%. Bradda is targeting a 2023 start for this Study, with a previously highlighted opex. target of c.$4000/t of LCE equivalent.

· Acid leach results from the upgraded concentrate sample continue to be impressive, indicating >98% lithium extraction to solution within 1 hour using a 90°c sulphuric acid leach approach at atmospheric pressure.

· In addition to impressive Li extraction from beneficiated Li clay, the Company is also working to recover co-products which will enhance the cash-flow and feasibility of the project.

· Bradda is continuing its metallurgical process test work on a larger bulk sample of its Li clay (150kg) with an aim to produce battery grade LCE Product (see PR dated 07 June 2022).

· Bradda is targeting to grow its resources at its Basin project this year with the upcoming drill programmes at BEE and BN. Bradda has two royalty payments due from expanding its resources at its clay claims (see PR dated 22 December 2021). The next payment of US$2.5m is paid on Bradda expanding its resource base to 1Mt LCE, and then the third payment of US$3m is achieved when Bradda expands its resource base to 2.5Mt LCE. Bradda is working with its geologists to hit these targets as soon as is feasible with the programmes mentioned above and the planned programmes at Basin West and West Extension.

Charles FitzRoy, CEO of Bradda Head Lithium, commented:

"Bradda Head Lithium is progressing the development of its lithium clay-hosted assets in Arizona. To complement our consistent reporting of exploration results we are now delighted to highlight further encouraging results from the second stage of our Phase 1 metallurgical test work programme with core from our 2021 Basin East drill programme. These results demonstrate the potential to commercially concentrate our Li clay grade by 26% to 1,900ppm Li and then, using a simple sulphuric acid leach approach at atmospheric pressure, use standard extraction equipment to extract more than 98% of the Li within an hour. We look forward to continuing our test work programme for bulk Cyclone Classification and Li extraction with co-products with US firm RDi, particularly now that we are well-funded via the recent fundraise in April (PR dated 11 April 2022).

"Alongside this timely new test work initiative on our 'lithium-in-clay' deposits, Bradda Head has commenced drilling at San Domingo, our pegmatite project in Arizona (see PR dated 18 July 2022).  7,000 metres of drilling in total is planned over the next 4 months at this potentially sizeable lithium-in-spodumene-style deposit. Importantly, Bradda has increased the ground under license by 75% recently and is aware of larger companies licensing ground proximate to us also to explore for Lithium."

"Work is underway on all three separate lithium projects in Arizona and Nevada (the Li pegmatite opportunity at San Domingo, Arizona, the 'lithium-in-brine' opportunity in Nevada, as well as the lithium-in-clays in Arizona), with results being reported as they become available.

"This continues to be a very busy and exciting time for all of us at Bradda Head as we push forward in this lithium-hungry market space, particularly in the USA."

Table One

	Weight per tonne/ LCE @ 1,500ppm	Weight per tonne/ LCE @ 1,900ppm	Reduction %
Li2CO3/ tonne	1.00	1.00	0%
Iron sulphate in PLS	5.94	4.11	31%
Magnesium sulphate in PLS	67.72	54.35	20%
Potassium sulphate in PLS	1.64	0.94	43%
Manganese sulphate in PLS	0.15	0.13	16%
Sodium sulphate in PLS	2.19	0.76	66%
Aluminium sulphate in PLS	8.85	4.78	46%
Acid Consumed / tonne LCE	81.23	61.13	25%

Background

Previous metallurgical test work conducted by Bradda in 2016 to 2018 proved that it was possible to extract 78% to 91% of the contained lithium from Burro Creek East clays, using acid-leach technology at 70°c, into an intermediate product. An 80% recovery was identified using an alternative roasting technology.

These follow-up test results demonstrate the rationale for follow-up metallurgical studies to develop on the exciting initial results.

Bradda has 47km² of clay claims (with the bulk of its clay assets stretching over 25km) ( https://www.braddaheadltd.com/media/image-library/2021-claim-staking/ ) around it's Basin and Wikieup licences. These license areas appear to have shared/similar lithium minerology. This license package is expected to provide a significant increase in the future resource growth profile in this lithium district, as only 2% of the licence area was drilled prior to 2021.

In light of the recent results from the 2021 Basin East drill programme, and developments in clay processing technology by its peers, Bradda undertook fresh metallurgical test work programmes to test mineralogy, PSD, Li beneficiation and lithium extraction rates by simple acid leach of lithium clay.

Bradda supplied SGS with samples of its Li clay from its 2021 Basin East drill programme. The samples were blended to form a representative sample from the same hole. The head sample was then assayed for full elemental analysis for lithium and all other impurity elements by ICP and XRF methods.

Mineralogical testing was then carried out by an XRD (X-Ray Diffraction) process to identify the mineral constituents.

Mineralogical analysis using XRD by SGS confirmed that most of the Li is in swinefordite mineralogy with a small fraction in petalite form. As is well-known, swinefordite form can be easily digested with acid without any calcination, or costly mineral processing processes.

The head sample was then screened to determine PSD and the various size fractions were weighed and analysed. This was helpful to determine future courses of action to concentrate the lithium in the clay. Based on this concept test, Cyclone Classification was considered a suitable commercial process to upgrade Li from the run-of-mine (ROM) Li clay.

The initial work demonstrated the potential to upgrade the Li content by 15% (from c.1,300ppm to 1,500ppm) and the follow-up commercial viability concept lab Cyclone Classification test at SGS showed that it was possible to upgrade Li content in the Li clay by a further 26% approximately (from 1,500ppm Li to 1,900ppm Li) by choosing O/F (Over Flow) fraction of average PSD of 5 microns. This could easily be achieved by any commercial Cyclone Classification process and would not be expected to involve heavy mineral processing costs.

This was followed by lithium extraction of a small sample to determine the extraction rate of lithium (98% within 1 hour) and other acid-soluble-associated impurities by acid leach. The results of this test work have helped determine the acid consumption of all the acid-soluble elements in the mineralised clay. This will be helpful for us to determine the future course of action to reduce acid consumption. Acid consumption will improve further on beneficiation of Li content in Li clay. However, currently it is also within manageable levels.

As is evident from the initial assays, the possible acid consumers, such as Mg, Al, Fe, Ca etc., are present in varying amounts in the lithium-mineralised clay. The beneficiation of Li clay will help in reducing these acid consuming gangue materials.

Interestingly, Li extraction at 98% by acid leach suggests that Li not only from swinefordite form, but also from petalite form, is digested.  It appears that fluorine present in Li clay in small quantities may have helped to catalyse and convert the crystal structure of petalite, and digested Li under normal acid leach. Bradda is working to try to understand this mechanism of action but is pleased to report extraction of nearly all Li from the Li clay.

As stated above, Bradda is now carrying out further metallurgical tests at RDi in the USA on bulk samples to develop PDC (Process Design Criteria) for an engineering cost study (ECS) to complete the PEA.

Note: Conversion factor of Li metal to lithium carbonate (LCE) = 5.323

For further information please visit the Company's website: www.braddaheadltd.com

Contact:

Bradda Head Lithium Limited	[phone]
Charlie FitzRoy, CEO Denham Eke, Finance Director
Beaumont Cornish (Nomad) James Biddle/Roland Cornish	[phone]
Peterhouse (Joint Broker)	[phone]
Charles Goodfellow Duncan Vasey Lucy Williams
Shard Capital (Joint Broker)	[phone]
Damon Heath Isabella Pierre
Red Cloud (North American Broker)	[phone]
Joe Fars
Tavistock (PR)	+ 44 20 7920 3150
Nick Elwes Adam Baynes	[e-mail]

Qualified Person BHL

The information in this announcement has been reviewed by Jim Guilinger, COO of Bradda Head Lithium. Mr. Guilinger is a graduate of the University of Colorado - Boulder, with a BA in Geology and with more than 40 years' experience in mineral exploration and mining geology, and is a qualified person under the AIM Rules. Mr. Guilinger consents to the inclusion of the technical information in this release and the context in which it appears. 

Notes to Editors

Bradda Head Lithium Ltd. is a North America-focused lithium development group. The Company currently has interests in a variety of projects, the most advanced of which are in Central and Western Arizona: The Basin Project (Basin East Project, and the Basin West Project) and the Wikieup Project.

The Basin East Project has an Indicated Mineral Resource of 17.6Mt at an average grade of 912ppm Li and 3.4%K for a total of 86kt LCE and an Inferred Mineral Resource of 57.6Mt at an average grade of 717ppm Li and 3.3%K for a total of 220kt LCE. In the rest of the Basin Project SRK has estimated an Exploration Target of between 300 and 1,300Mt of material grading between 600 and 850ppm Li which is equivalent to a range of between 1 and 6Mt LCE.

The Group intends to continue to develop its three phase one projects in Arizona, whilst endeavouring to unlock value at its other prospective pegmatite and brine assets in Arizona, Nevada, and Pennsylvania.

All of Bradda Head's licences are held on a 100% equity basis and are in close proximity to the required infrastructure.

Bradda Head is quoted on the AIM of the London Stock Exchange with the ticker of BHL and on the US OTCQB market with a ticker of BHLIF.

 

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