Robert’s areas of expertise and interest encompass trace element and isotope geochemistry as archives of Archaean surface conditions, crust formation and evolution, geochronology and petrochronology using LA-ICP-MS, and geochemical and isotopic fingerprinting of stone artefacts. His wide range of research interests and activities is reflected in > 90 peer-reviewed publications. 

Robert is responsible for the management of all NRF-funded instruments. He is also currently the main operator of the Element XR, coupled with the laser. Using LA-ICP-MS, he established routine analytical protocols for U-Pb dating of a wide range of minerals, including zircon, apatite, xenotime, rutile, titanite, epidote, hematite and carbonate. Presently, the team is setting up LA-ICP-MS-based compositional and isotopic mapping. Robert is also involved in developing Ca, Ti, Fe, Cu and Zn stable isotope techniques utilising the collision cell MC-ICPMS. 

Robert obtained his Diplom (MSc equivalent) at the Johannes Gutenberg University in Mainz (supervision Prof Uwe Ring) and completed his PhD at the University of Melbourne (Profs Jon Woodhead and Janet Hergt). Subsequently, he was employed as postdoctoral fellow at the University of Queensland (Profs Balz Kamber and Ken Collerson) and the University of Canterbury (Prof Steve Weaver). While employed in the resource industry, he completed a degree in geostatistics. During his PhD studies and postdoctoral employment, he received training in a wide range of analytical methods, including chromatographic ion exchange, MC-ICP-MS and TIMS. Robert is a NRF-rated B2 scientist, a Fellow of the GSSA, a SACNASP-registered Professional Natural Scientist and member of the International Association of Geo-Analysts. He presently serves on the editorial team of Chemical Geology. 

Email: robert.bolhar@wits.ac.za 

Grant is passionate about isotope geochemistry and applying this powerful geochemical toolbox to a range of problems in hard-rock geoscience, as well as paleo- and environmental sciences. Grant’s research focuses on using the isotope geochemistry of magmatic rocks to understand and explain magmatic processes operating throughout Earth’s continental crust. While maintaining a strong focus on solid earth geochemistry and geodynamics, his developing research links an understanding of geochemistry with surficial processes (be it natural or human processes) and the impacts on individuals and society. One such research thrust involves using heavy, stable metal isotope isotopes of Ca, Cu, Fe and Zn as probes of paleodiet, trophic level and paleoecology in fossil hominids, dinosaurs and mammals, especially as proxies of how past environments respond to and recover from environmental stress and extinction events.

Grant works in the ultra-clean lab and the mass spec lab supervising users, training new students, developing new isotopic methods and running his own research samples. 

Grant received his PhD at Wits University, supervised by Lew Ashwal, and focused on using isotope geochemistry in understanding the petrogenesis of enigmatic Proterozoic massif-type anorthosites. Grant started his career at Wits University in 2014 as a lecturer and is currently an Associate Professor. Between 2011 and 2012, Grant was a Predoctoral Fellow at the Department of Terrestrial Magnetism at the Carnegie Institution for Science (now Earth and Planets Lab). 

Email: grant.bybee@wits.ac.za 

Karen’s research interests are focussed on natural diamonds and their mantle host rocks. Her research has included studies that use mantle xenoliths and diamonds to investigate the mineralogical properties of the deep Earth; tectonic processes that affect the mantle and result in the formation, stabilisation and destruction of continents; and using diamonds as the ultimate tracer of the deep carbon and nitrogen cycles. 

Karen joined Wits as a Senior Lecturer in 2022, and oversees solution Rb-Sr, Sm-Nd, and Lu-Hf isotope analyses of a range of geological and paleontological samples on the NuTIMS and NuSapphire. She is also involved in method development of non-traditional isotopes including Fe, Cu, Zn, K, and Ca. 

Karen earned a MSc in Geochemistry from the University of Cape Town (South Africa) in 2008, analysing Re-Os isotopes in sulphide inclusions in Ellendale diamonds (with John Gurney, Steve Richardson, Steve Shirey, Anton le Roex and Craig Smith). Karen received her PhD in Geology from the University of Alberta (Canada) in 2013, using peridotites and eclogites from the Attawapiskat kimberlites to understand the age and evolution of the Superior craton (with Thomas Stachel and Graham Pearson). Between 2014 and 2020, she was based at the Gemological Institute of America (NYC), first as a Postdoctoral Fellow, then as Research Scientist. 

For Karen’s full CV and publications, please see the following link

Email: karen.smit@wits.ac.za 

Saumik is an environmental geochemist, and joined Wits University as a Lecturer in October 2024. His research interests focus on understanding various environmental processes, including chemical weathering, climate change, and environmental pollution, using geochemical tools such as trace element composition and their isotopic composition. Saumik is the WIGL laboratory manager, committed to training users to work in the ultraclean laboratory to prepare samples for isotope analyses. Saumik is also involved in developing methodologies to determine non-traditional isotopes such as Fe, Cu, Zn and K. 

Saumik pursued his master’s from Jadavpur University, India, and received his Ph.D from Indian Institute of Science Education and Research Kolkata (IISER Kolkata), India. His doctoral thesis focused on understanding sources, cycling, and fluxes of trace metals from the Ganges River System. Between 2018 and 2024, Saumik worked as a postdoctoral researcher at Stellenbosch University, South Africa. During this time, Saumik actively participated in various research operations focused on marine and atmospheric geochemistry. 

Email: saumik.samanta@wits.ac.za 

Marlin is responsible for managing the XRF and quadrupole ICP-MS instrumentation, along with a clean-lab dedicated to digestion and sample preparation for trace element analyses. Marlin supervises and trains many lab users. 

Marlin received his MSc in Biochemistry at UKZN and joined Wits as a Lab Manager in 2008.

Email: marlin.patchappa@wits.ac.za 

Scott is interested in Archean crustal dynamics, the controls on Earth’s long-term climate evolution and critical metal mineralisation processes. Scott integrates field geology with laboratory-based geochemistry and geochronology to investigate these processes.

Scott earned an MSc degree at the University of Cape Town working on the Barberton Greenstone belt. After working in the mineral exploration industry for two years Scott went on to complete his PhD at Princeton University focussing on TIMS U-Pb geochronology applied to the eastern Pilbara craton and Neoproterozoic rocks in northern Ethiopia. Scott then held a postdoctoral position at the University of Arizona where he helped develop novel stable isotope measurements of elements like Zr and Hf.

Scott started as a senior lecturer at Wits University in 2022 and is using the new geochemical tools available in the School of Geosciences to investigate southern Africa’s rich geological record. Along with Robert, Scott oversees LA-ICP-MS analyses, and is also setting up ID-TIMS U-Pb zircon geochronology.

Email: scott.maclennan@wits.ac.za 

Rachel is a research assistant where she assists in both the Mass Spec Lab and the Clean Lab with sample preparation, user training, method development, and instrument support. 

Rachel is currently pursuing a PhD in Chemistry, focusing on the geomorphology and geochemistry of wetland systems in the Overberg region (with Prof. Marc Humphries and Prof. Susanne Grenfell - Stellenbosch). She holds a BSc in Chemistry with Chemical Engineering and an MSc in Chemistry with distinction (with Prof. Marc Humphries and Dr. Lynne Quick). Her MSc research focused on palaeoclimate reconstruction along the Southern Cape coast through geochemical analysis of a sediment core, providing insights into past climatic conditions and climate drivers. 

Her broader research interests lie in environmental and isotope geochemistry, particularly the use of trace metal and isotope signatures to assess contamination, track biogeochemical processes, and explore ecological impacts. She is currently involved in collaborative projects investigating metal, plastic, and pesticide contamination in various ecosystems. Rachel also has a strong interest in recent palaeoclimate reconstruction and its application in understanding and predicting climate change.

In addition to her research work, Rachel has a background in laboratory quality management, with experience supporting ISO 17025 compliance in analytical laboratories. 

Email: rachel.mey@wits.ac.za 

Allan is Professor Emeritus in the School of Geosciences, and has published nearly 200 scientific papers. Some of his most important discoveries are the previously unknown basal ultramafic succession of the Bushveld Complex, evidence for the most Mg-rich magmatic olivines on Earth and the highest temperature komatiite lavas ever recorded. 

Allan Wilson established the Earth Lab in the School of Geosciences in 2006, which included XRF instruments, Quad ICP-MS instruments, as well as an ultra-clean preparation lab. 

Allan is an Honorary Life Fellow of the Geological Society of South Africa and a previous recipient of the Draper Medal, the highest scientific award of the Geological Society of South Africa for exceptional contributions to the advancement of South African Earth Science.

Email: allan.wilson@wits.ac.za