Our Staff

Key personnel

Maelgwyn Mineral Services Africa currently employs 25 people of which 22 are managerial/technical staff and 3 are administration.

John Batty

General Manager

John has a BSc in Chemical Engineering from the University of the Witwatersrand and has over 30 years’ experience working in the mining industry.  John worked for Gencor / Billiton / BHP Billiton where the initial part of his career was spent working in a production environment on gold mines in both South Africa and Brazil. John then moved into R&D and spent many years working on bioleach development for gold and also base metals.

John’s expertise is in refractory ores where he has experience in roasting, pressure oxidation and bioleaching. John was the Manager of Process Engineering at BHP Billiton and then moved to SGS South Africa where he managed the Metallurgy and Mineralogy division. Prior to joining Maelgwyn he was the Business Development Manager for Mintek.

Peter Lotz

Gold Process and Environmental Manager

Peter holds a BTech degree in organic chemical synthesis from Basel, Switzerland. His work experiences include working in the chemical R+D environment (5 years, CIBA-GEIGY, Switzerland), environmental technology field (7 years, DOLDER, Switzerland) and metallurgical R+D (5+15 years, MINTEK, South Africa). He was one of the module leaders in AMIRA’s P497 project on cyanide deportment around tailings dams. The last position at MINTEK was the one of Head: Gold Process & Environment where he was responsible for directing the research and commercial testwork project work of a group active in the global gold sector.

His areas of expertise include gold leach technology, refractory ores, cyanide management (including cyanide mass balancing, destruction and analytical methodologies) as well as general mining related sustainability issues (arsenic, water management). He is a listed ICMI cyanide management code auditor and has actively participated in the formation of the code as well as many gap and certification audits.

Hennie Stallknecht

Metallurgical Manager and Flotation Specialist

Hennie holds a National Higher Diploma in Extractive Metallurgy from the Wits Technicon in Johannesburg. He has over 40 years’ experience in laboratory and pilot plant scale technology development, plant operation and optimization. During this time he was employed by JCI, The South African Chamber of Mines, BHP Billiton (Head of Minerals Engineering), Mintek and as Manager of Flotation Technologies with SGS Lakefield Research Africa.

Key areas of expertise include management of minerals beneficiation projects for base metals, precious metals and industrial minerals on laboratory and pilot plant scale. Specific experience includes froth flotation, gravity separation and heavy medium separation and associated flow sheet development.

Stephen Stone

Manager Finance and Administration

Stephen started his studies in financial accounting and auditing in 1984 and graduated at Rand Afrikaans University while completing his articles with PriceWaterhouseCoopers (PWC) firm of chartered accountants. He is a practicing financial accountant and tax practitioner with more than 30 years working experience in the financial sector.

Stephen has a unique combination of skills in the following areas: Financial accounting  reporting and analysis, Corporate and personal taxes, business strategy and development, board governance and company secretarial practice, risk management, management, project management and negotiation.

He joined Maelgwyn in 2012 and has also worked for Brigadiers Motion Picture Company, Protekon (Division of Transnet) and UWP Consulting Engineers.

Stephen is a registered CIPC agent and SARS Tax Practitioner and holds memberships with The South African Institute of Chartered Accountants (SAICA) (Practicing) and the South African Institute of Professional Accountants (Practicing).

Juan van der Merwe

Business Development Manager

Juan holds a BSc in Chemical Engineering from North West University and a BCom in Business Management from the University of South Africa. He has 12 years’ experience in the mining industry and fulfilled the roles of Production Metallurgist at Gold Fields, Head of the Gold Technologies at SGS South Africa and more recently Laboratory Manager at MMSA.

Areas of expertise include gravity separation, froth flotation, gold and base metal leaching, as well as cyanide destruction.

Sonestie Janse van Rensburg

Laboratory Manager

Sonestie has 12 years’ experience in leaching, pre-feasibility and feasibility testing for process flowsheet design, with the last 8 years focussed on gold leach optimisation and gold related environmental issues.

She is qualified with a Master’s Degree in Biochemistry (Warwick University, UK) and successfully completed a Master’s Degree Course in Hydrometallurgy Engineering (presented by Dr Mike Nicol, University of Cape Town).

She worked at MINTEK as a Gold Project Leader/ Process Engineer for 9 years and prior to that worked at BHP Billiton as a Junior Engineer.

Makhora Kgwahla

Research and Development Manager

Makhora holds a BTech in Laboratory Management from Tshwane University of Technology as well as a National Diploma in Analytical Chemistry from Wits Technicon and has over 14 years’ experience in mining laboratories. He began his career as an Analytical Chemist at Impala Platinum Refinery before joining BHP Billiton as Technical Assistant. Makhora then moved to Gabon to set up an analytical laboratory to support the mineral exploration division as Laboratory Specialist.

Area of expertise include leaching, froth flotation and the inspection and maintenance of MMSA’s deployed technology.

Solomon Mogashoa

Applications/Process Engineer

Solomon holds a BEng degree in Metallurgical Engineering from University of Pretoria and has 6 years’ experience in the gold mining industry. He started his career with Gold Fields / Sibanye Gold as a Production Metallurgist where he was instrumental in commissioning and optimisation of the world’s first acid 1000 online lime analyser.

Areas of interest are general hydrometallurgical leaching processes, metals recovery as well as cyanide management (commissioning and optimisation of cyanide destruction processes).

Solomon joined MMSA in 2014 and is responsible for the commissioning, inspection and related maintenance of MMSA’s deployed technology across sub-Saharan Africa

Zwanga Ratombo

Manager: Supply Chain and Logistics

Zwanga holds a BSc Metallurgical and Materials Engineering from the University of Witwatersrand and has 5 years of experience in the gold mining industry. He started his career at Sibanye Gold where he fulfilled the role of Production Metallurgist.

He joined MMSA in 2019 and his job description includes but not limited to supply chain, quality control and maintenance of the Laboratory Equipment and Aachen Technology.

Koketso Busang


Koketso has a Btech Degree in metallurgical engineering from the Tshwane University of Technology and she is currently completing a BSc Hons in extractive metallurgy at the University of Pretoria.

She commenced her career as a trainee metallurgist at Tharisa Minerals and spent 2 years with Senmin International’s research and development laboratory as a metallurgist, before joining MMSA.

Epiphania Mariba


Epiphania holds an MSc in Chemical Engineering from the University of the Witwatersrand. Her work experience includes 2 years spent at Anglo American Research where the main focus was piloting a hydrometallurgical process. After that she spent 4 years at Vanchem Vanadium Products as a Process Engineer in the Process Development department. The role involved day to day monitoring of the different processes used in vanadium production, new product development as well as carrying out process improvement testwork for implementation in the plant.

Mutshidzi Singo

Trainee Metallurgist

Mutshidzi holds a BTech degree in extraction metallurgy from the University of Johannesburg. She has worked at Mineral processing and Technology Research Centre at the University of Johannesburg as an intern where she was exposed into innovation and execution of metallurgical processes. Mutshidzi then completed her internship at Maelgwyn Mineral Services Africa where she gained experience on gold processing and other metallurgical processes.

Prince Thobela

Chief Leach Technician

Prince started at Barberton Mines in 1989 as a plant operator before moving on to the mine’s metallurgical laboratory as Met Lab assistant in 1993 until 2005. In 2005 he joined MMSA as supervisor for the Imhoflot flotation plant at TGME mine. In 2010 he was transferred to the MMSA laboratory when TGME mine closed down.

Lomax Sani

Chief Flotation Technician

Lomax started at Mintek as a flotation laboratory assistant then became a flotation laboratory technician, before joining SGS Johannesburg as a senior flotation technician. He has over 12 years’ experience in laboratory and pilot plant flotation.

Physical Address

1331 Staal Street (corner Spokeshave)
Stormill Ext 2
South Africa

Postal Address

PO Box 2437
South Africa

Contact Details

Tel: +27 11 474 0705
Fax: +27 11 474 5580
Maelgwyn Mineral Services Africa (Pty) Limited | South Africa | Company Reg No: 2003/007416/07
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