Hope & Gorob Ore Sorting Optimisation
12 February 2025
Bezant Resources PLC
("Bezant" or the "Company")
Hope & Gorob Ore Sorting Optimisation
Bezant Resources ("Bezant" or the "Company") is pleased to announce the successful completion of ore sorting optimisation on copper - gold ore from the Hope & Gorob Project, Namibia.
Optimisation on future run of mine ore derived from fresh drill core twinned with historic drilling exceeded grade and recovery requirements used in the Company's financial model for the Project. Results confirm previous projections that Project capital payback can be achieved within less than 20 months of full-scale production.
Highlights
· Optimisation tests confirmed that ore sorting and pre-concentration can produce the required mill feed volumes at a grade consistent with financial modelling inputs of contained copper.
· Project evaluation requires a feed grade of 2.4% Cu. Ore sorting tests returned a feed grade of up to 2.95% Cu with substantial gold and silver credits also applicable.
· Current financial evaluation and projected returns have been achieved and well-exceeded based on optimisation.
· The study specifically tested mineralisation to be encountered within the first three years of production and indicate that payback of capital in less than a 20 month period remains achievable.
· The study revealed a high percentage of chalcocite (copper content 79.9%) preferentially reporting to fines generated during crushing due to its high friability. This enrichment results in:
o Minimisation of the dilutionary effect of fines on mill feed grade
o Reduces pressure on mill capacity
o Provides scope for additional mill feed to fill the extra capacity due to higher fines content
· Based on visual observations by the metallurgical consultant the quantity of sulphide-rich Cu mineral species reporting to fines fraction was found to be up to 20% higher than projected which is beneficial for the downstream processing flow sheet and overall copper recovery.
· Recovered gold grades confirmed expectations. External Resource Estimation allocated an average gold grade of 0.41 g/t Au to the Hope Resource. Calculated from the assay results the optimisation study returned an average grade of 0.42 g/t Au.
· Silver grades significantly exceeded expectations and the figures used in the current financial model. The optimisation study returned an average Run of Mine grade of 31 g/t Ag calculated from the test work assay results.
· Ore sorting tests were based on a combination of conductivity, XRF and colour sensors. Sorting successfully separated high density sulphide-rich mineralisation and low density copper oxide mineralisation from perceived waste and clearly achieved set objectives.
· Mass balance calculations identified a significant quantity of copper currently classified as waste which was recovered by ore sorting. The implication being that additional optimisation may further increase contained copper recovery to the benefit of the Project once the source of this additional copper is understood. The current view is that fine-grained copper may be reporting to low density quartzite that has previously been assumed to be a waste product.
Colin Bird, Executive Chairman of Bezant, commented "Ore sorting optimisation test work has been very successful, and results have more than met the requirements of our financial model. There is scope for further improvement in copper recovery particularly from material currently reporting to waste.
The results justify our commitment to ore sorting technology that not only allows us to operate efficiently in a challenging environment but also in a manner that is more beneficial for the environment. Excellent advice and guidance from the ore sorting experts at Steinert have further improved Project economics with scope for yet further improvements in copper recovery being possible.
We look forward to providing further updates as we move towards project development".
Ore Sorting Optimisation Study
Current financial evaluation and projected returns have been based on the premise that 180ktpa of pre-concentrate can be produced from 480ktpa of RoM mined (37.5% mass yield) at a grade of 2.4% contained Cu. Test results have indicated that these base financial model inputs have been achieved and well exceeded.
The ore sorter test work was conducted on a sample representing the first 3 years of production as per a detailed mining schedule and design developed generated by external mining engineering consultants. The geological Resource model developed by independent Resource consultants (upon which the mine design was based) indicated that the average grade of the sample retrieved would be approximately 1.36% Cu.
Sensor readings coupled with assay results indicate that there is at least 15% of ore in the waste fraction (mining dilution) that contain mineralised material similar to the final sorter product and is subsequently recovered by the ore sorter. This equates to an increase in mined feed grade to the pre-concentration circuit being 0.2-0.4% Cu higher than predicted by geological and Resource modelling and presents upside to current mine design and financial modelling.
Chalcocite (high Cu content) preferentially reports to crusher fines due to its high friability resulting in a Cu enrichment of the fines material during crushing. This grade increase is substantially higher than previously predicted which in turn minimises the dilutionary effect of the fines on mill feed grade.
Au and Ag content in the ore body were only partially credited for in the Resource block model but from test results the Au grade achieved in the pre-concentrate (mill feed) is consistent with the projected grades used in the DCF. The Ag grades achieved were significantly higher (factor of 5 higher than modelled) which does present upside on sales revenue receivable.
Background
In order to validate recoveries and grades achievable from current mine and pre-concentration circuit designs, Bezant Resources commissioned a pilot plant level metallurgical test work campaign based on a bulk sample recovered from within current pit shell design. The bulk sample consisted of PQ drill core material from a dedicated drilling campaign performed with the location and selection of the drill hole positions informed by the current geological model and mine design and corresponding with the first 3 years of production.
Sample collection
A drilling programme was managed internally by Bezant geological personnel. Once sample intervals had been selected and logged the samples in sealed core trays were delivered to a recognised assay laboratory where a metallurgical consultant took receipt of the samples for sample preparation and maintenance of the chain of custody.
The sample selection and location were based on the following:
· The selected drill hole positions were informed by the current geological model and mine design and include material from the first 3 years of operations.
· Sample included all minerals species present and represents the typical mineralogical profile expected to be processed during the first 3 years of production including both Sulphide and Oxide mineral species.
· All drillholes were twinned with historical geological drillholes for reference purposes and all internal waste between mineralised zones was included in core samples.
· An additional 300-500mm of hanging wall and footwall waste was included in each sample to allow for potential mining dilution of 10-15%.
· Where the height of core sampled was less than 3m additional hanging wall and footwall material was included in the sample to ensure that the sample corresponds with mining bench heights of 3m.
· Weighted average calculated grade of the core sample based on geological data was determined to be 1.36% Cu. For the geological grade calculation waste was accounted for as having 0% Cu content which is consistent with the methodology followed during geological modelling as well as for mine design purposes.
Crushing and screening
For ore sorter calibration three sections of core was identified by the Chief Geologist that typically represents Sulphide (High Density), Oxides (Low Density) and waste with little to no mineralisation visibly present. These samples were crushed, screened and bagged separately from the balance of the sample for calibration purposes and were only added back to bulk sample on completion of sorter calibration.
The four samples (3 calibration samples and 1 RoM sample) were crushed and screened by TEA Metallurgical Laboratory (Swakopmund, Namibia) personnel under the supervision of Bezant Consulting Metallurgist. After crushing the material was screened at a screen size of 17x50mm with all oversize material (>50mm) returned for further crushing until 100% passing 50mm was achieved for ore sorter feed. The total coarse (>17mm material) and fines (<17mm) samples were individually bagged and weighed to determine crusher fines generation.
Ore sorter pilot tests
Ore sorter test work was conduct at the Steinert 1.2m ore sorter unit located in Namibia and managed by Steinert personnel.
The ore sorter was operated at three different settings using a colour camera and inductive sensors with XRT sensors as background screening with three different products being generated at the different sensing intensities selected. The three product streams and one waste stream were collected in labelled bulk bags and returned to TEA Metallurgical Laboratories for mass determination and assay.
On receipt at TEA labs the samples were individually weighed, reconciled and subsamples split out using a 12-way rotary sample splitter to produce an aliquot for assay purposes.
The fines generated during test work material handling predominantly reported to the Drop sample and were screened out and weighed to determine mass of fines that would be below detection limits of the sorter.
Sample losses during the test campaign due to lock up in system, spillage or handling was also determined to be 3.8% of original sample collected.
Conclusions
The main aim of the test campaign was to validate whether the pre-concentration circuit could produce the required mill feed volumes at an acceptable grade of contained Cu (2.4%). From the test results it is apparent that this aim was successfully achieved with mass yields exceeding 50% compared to the required 37.5% mass yield while pre-concentrate grades ranged between 2.4 and 2.95%.
When considering the sulphur content of the sorter product streams it is apparent that the ore sorter system can successfully differentiate and subsequently recover sulphides from the RoM material to produce suitable mill feed material.
In addition to the successful recovery of sulphide species, the use of a colour camera system has also shown that it can successfully identify Cu oxide species (such as Malachite) and recover this material from the feed stream.
The outcomes of this test campaign over a wide area of the Hope deposit would indicate that actual RoM grades may potentially be significantly higher during operations than currently being projected.
Au and Ag content in the deposit was given little consideration in geological Resource modelling even though grab samples indicated the presence of these at elevated levels in certain areas at the Hope prospect. From the test results achieved it has been shown that Au and Ag is prevalent in the majority of the deposit and especially Ag grades are significantly higher than projected.
Additional ore sorter optimization test work could further improve product grades and reduce Cu losses to waste. These additional tests could include removal of quartzite-magnetite to waste which is currently reporting to the product stream. Additionally, a two-stage sorting system can also be tested and potentially installed to separate oxide and sulphide species from the product stream for these to be treated separately in downstream processes.
Further geological investigation into the mechanism for Cu deportment in perceived waste rock can also be completed. Considering that the ore sorter has illustrated that it can successfully identify and recover any Cu material from even low-grade waste feed implies that potentially significant portions of what is currently classified and mined as barren waste could still be economically processed by the sorter to generate additional feed material for downstream flotation processes. This would significantly increase the amount of economically extractable Cu in the deposit.
For further information, please contact:
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Bezant Resources Plc Colin Bird Executive Chairman |
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Beaumont Cornish (Nominated Adviser) |
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Novum Securities Limited (Joint Broker) Jon Belliss |
+44 (0) 20 7399 9400 |
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Shard Capital Partners LLP (Joint Broker) Damon Heath |
+44 (0) 20 7186 9952 |
or visit http://www.bezantresources.com
The information contained within this announcement is deemed by the Company to constitute inside information as stipulated under the Market Abuse Regulations (EU) No. 596/2014 as it forms part of UK Domestic Law pursuant to the Market Abuse (Amendment) (EU Exit) regulations (SI 2019/310).
Beaumont Cornish Limited ("Beaumont Cornish") is the Company's Nominated Adviser and is authorised and regulated by the FCA. Beaumont Cornish's responsibilities as the Company's Nominated Adviser, including a responsibility to advise and guide the Company on its responsibilities under the AIM Rules for Companies and AIM Rules for Nominated Advisers, are owed solely to the London Stock Exchange. Beaumont Cornish is not acting for and will not be responsible to any other persons for providing protections afforded to customers of Beaumont Cornish nor for advising them in relation to the proposed arrangements described in this announcement or any matter referred to in it.
Forward Looking Statements:
Certain statements in this announcement are or may be deemed to be forward looking statements. Forward looking statements are identified by their use of terms and phrases such as ''believe'' ''could'' "should" ''envisage'' ''estimate'' ''intend'' ''may'' ''plan'' ''will'' or the negative of those variations or comparable expressions including references to assumptions. These forward-looking statements are not based on historical facts but rather on the Directors' current expectations and assumptions regarding the Company's future growth results of operations performance future capital and other expenditures (including the amount. Nature and sources of funding thereof) competitive advantages business prospects and opportunities. Such forward looking statements reflect the Directors' current beliefs and assumptions and are based on information currently available to the Directors. A number of factors could cause actual results to differ materially from the results discussed in the forward-looking statements including risks associated with vulnerability to general economic and business conditions competition environmental and other regulatory changes actions by governmental authorities the availability of capital markets reliance on key personnel uninsured and underinsured losses and other factors many of which are beyond the control of the Company. Although any forward-looking statements contained in this announcement are based upon what the Directors believe to be reasonable assumptions. The Company cannot assure investors that actual results will be consistent with such forward-looking statements.
Qualified Person:
Technical information in this announcement has been reviewed by Eugene Nel. Mr Nel graduated with a B.Tech degree in metallurgical engineering from the Tshwane University of Technology and has subsequently worked for over 30 years as metallurgist, senior metallurgist, operations manager and consultant at various companies including Samancor Chrome and Impala Platinum.
Since 2005 he has been consulting to the minerals beneficiation industry globally and has been involved in several projects in assisting client teams throughout the project lifecycles and disciplines.
He is registered as Pr.Tech.Eng with the Engineering Council of South Africa and a member of the Southern African Institute of Mining and Metallurgy (SAIMM) and Mine Metallurgical Managers Association of South Africa (MMMA). Based on his experience and professional affiliations he is qualified as a Competent Person for metallurgy under the various reporting codes. Mr Nel has reviewed and approved this announcement.
Glossary
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"chalcocite" |
A copper sulphide mineral, Cu2S, found in zones of secondary enrichment of copper ores
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"DCF" |
Discounted Cash Flow
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"footwall" |
The mass of rock below a fault, vein or bed of mineralisation
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"g/t" |
Grams per tonne
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"hanging wall" |
The mass of rock above a fault vein or bed of mineralisation
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"inductive sensor" |
Non-contact sensor that uses electromagnetic fields to detect metallic objects within its sensing range
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"magnetite" |
A magnetic iron oxide, Fe3O4
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"malachite" |
A green copper carbonate mineral (Cu2(OH)2CO3) which forms by alteration of copper sulphide minerals
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"oxide" |
Minerals produced by natural weathering processes at or near the earth's surface
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"quartzite" |
A silica rich metamorphic rock formed from sandstone
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"RoM" |
Run of mine
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"sulphide" |
A metallic compound of sulphur
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"XRF" |
X-ray fluorescence
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"XRT sensor" |
X-ray transmission (XRT) used to separate materials based on their density |
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