Kanye Project: Metallurgical Test Work Results
24 July 2023
Bezant Resources Plc
("Bezant" or the "Company")
Results from Phase 1 Metallurgical Test Work on Kanye Manganese Sample
Bezant (AIM: BZT) is pleased to provide information on encouraging results of Phase 1 metallurgical testing carried out by Wardell Armstrong International ('WAI') on a sample from its' 100% owned Kanye manganese exploration project in Botswana. The primary objective of the work was to investigate the amenability of extracting manganese from the Kanye mineralisation by sulphuric acid leaching.
· Sulphuric acid leaching successfully demonstrates an amenability to extract manganese from the Kanye sample into solution, with recoveries of up to 99.4% Mn achieved at a temperature of 60oC.
· Sulphur dioxide addition was found to have a direct correlation to the overall manganese recovery.
· Most tests demonstrated fast leach kinetics with relative manganese recoveries after 1 hour of leaching ranging up to 90.7%.
· Whole rock analysis showed relatively simple mineralogy, the main manganese mineral in the Kanye sample being pyrolusite, which is the chief ore mineral for mine production worldwide.
· Based on the encouraging initial results, Bezant has engaged WAI to carry out Phase 2 testwork to optimise the leaching parameters for economic processing of a manganese ore, whilst tracking other elements relevant to the economics of battery-grade manganese production.
Colin Bird, Executive Chairman of Bezant, commented:
"The first phase of metallurgical testing is highly encouraging in that we have demonstrated our ability to recover a high level of manganese. The next phase will move towards commercial optimisation of the leaching parameters, with specific emphasis on limiting sulphuric acid consumption. We are aiming for battery grade manganese production which is much sought after and we look forward to moving towards resource definition and a preliminary economic assessment."
Kanye Phase 1 Metallurgical Test Work
Wardell Armstrong International (WAI) was commissioned by Bezant to undertake a programme of metallurgical testing on a sample from the Kanye manganese deposit, Botswana. The primary objective of the testwork was to investigate the amenability of effectively extracting manganese from the mineralisation by sulphuric acid leaching. A secondary objective was to undertake a small programme of sample characterisation including chemical, XRF and XRD analysis.
X-Ray Fluorescence analysis on the whole rock samples was conducted to determine the weight percentage of major rock-forming elements. The results showed that the sample primarily consisted of silicon dioxide and manganese oxide constituents, with minor phases of iron oxide and aluminium oxide.
X-Ray Diffraction analysis on the whole rock sample was conducted to determine the weight percentage of individual mineral phases. The results showed that the sample primarily consisted of quartz, with lesser pyrolusite, goethite and talc.
WAI determined the Kanye composite to have a manganese head grade of 15.48% Mn obtained using an aqua regia digestion with an ICP-OES finish.
Six leach tests were conducted on the sample under varying conditions such as grind size, sulphur dioxide addition, and pH at a temperature of 60oC. A benchmark review of similar projects found sulphur dioxide to be an important parameter in the reduction of manganese to become more amenable to sulphuric acid leaching.
Table 1 - Whole Ore Acid Leach Test Results for Kanye Mn Sample
Grind Size (D80)
The relationship observed demonstrates that sulphur dioxide (SO2) addition has a strong correlation to the overall manganese recovery (Table 1). Overall manganese recovery ranges from 1.9% to 99.4% for 0.34kg/t to 500kg/t of sulphur dioxide addition for ALT1 and ALT3 respectively.
In ALT6, pH was increased from 1.0 to 1.5 to reduce the overall acid consumption over the course of the leach to obtain more economic conditions for processing. Sulphuric acid consumption was reduced from 246kg/t to 217kg/t resulting in a decrease of overall manganese recovery from 82.6% to 79.2% for ALT5 and ALT6 respectively.
Except for ALT1 and ALT2, where the resolution of the leach kinetics could be distorted as a result of poor recoveries, all tests demonstrate fast leach kinetics with relative manganese recoveries after 1 hour of leaching ranging from 84.9% to 90.7% for ALT6 and ALT3 respectively.
· WAI determined the Kanye composite to have a manganese head grade of 15.48% Mn obtained using an aqua regia digestion with an ICP-OES finish;
· X-Ray Fluorescence analysis found the major elemental oxide present in the sample is silicon dioxide, with lesser amounts of manganese, iron, and aluminium oxides at 63.83%, 17.94%, 6.02%, and 2.61% respectively.
· X-Ray Diffraction analysis found the major mineral phases present were quartz and pyrolusite at 71.4% and 10.4% respectively. This is comparable to the metal composition from XRF analysis.
Sulphuric Acid Leach Testwork
· Sulphuric acid leaching demonstrated an amenability to extract manganese from the sample into solution. Manganese recoveries of 99.4% could be achieved at a pH of 1.0 and sulphur dioxide addition of 500kg/t;
· Sulphur dioxide addition values were found to have a direct correlation to the overall manganese recovery;
· With the exception of ALT1 and ALT2, the leach kinetics of manganese recovery were shown to be fast, with relative leach rates after 1 hour ranging from 84.9% to 90.7% for ALT6 and ALT3 respectively;
· Acid consumption values ranged from 27kg/t to 477kg/t for ALT2 and ALT3 respectively;
· pH was shown to influence the overall manganese recovery with a decrease from 82.6% to 79.2% when pH was increased from 1.0 to 1.5 for ALT5 and ALT6 respectively.
Planned Phase 2 Test Work - WAI Recommendations
The primary objective is to continue from the previous phase of acid leach testwork to optimise the leaching parameters for economic processing of a manganese ore, whilst tracking a range of other elements relevant to the economics of battery-grade manganese production.
Specifically, WAI recommended the following:
· Undertake further optimisation leaching testwork to decrease the level of acid consumption over the course of the leach. This could include variables such as further grind size investigation at elevated recoveries, leach optimisation at elevated pH, increased temperature, and calcination pre-treatment;
· Track the recovery of other analytes that are likely to have an impact on the downstream purification process circuit of battery-grade manganese sulphate monohydrate production; and
· Consider maintaining a redox potential with the addition of sulphur dioxide throughout the leaching process at defined intervals, as opposed to a single, substantial addition at the beginning of the leach process.
For further information, please contact:
Bezant Resources Plc
Beaumont Cornish (Nominated Adviser)
Novum Securities Limited (Joint Broker)
+44 (0) 20 7399 9400
Shard Capital Partners LLP (Joint Broker)
+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).
Technical information in this announcement has been reviewed by Edward (Ed) Slowey, BSc, PGeo, technical director of Bezant Resources Plc. Mr Slowey is a graduate geologist with more than 40 years' relevant experience in mineral exploration and mining, a founder member of the Institute of Geologists of Ireland and is a Qualified Person under the AIM rules. Mr Slowey has reviewed and approved this announcement.
The following is a summary of technical terms:
Process of formation and concentration of elements and their chemical compounds within a mass or body of rock
A fine-grained laminated sediment