Meet The Team

Dr. Geoffrey Howarth is a Senior Lecturer at UCT, specialising in kimberlites, mantle xenoliths, diamonds, and planetary petrology. His research covers deep-Earth processes including melt–lithosphere interactions and diamond genesis, as well as planetary studies using Martian meteorites. After completing his PhD at Rhodes University and postdoctoral work in the U.S., he returned to UCT in 2019, where he co-leads the Kimberlite Research Group and curates the Diamond collection.

Professor Philip E. Janney is a mantle geochemist at the University of Cape Town, specialising in kimberlites, carbonatites, and mantle xenoliths. With a PhD from Scripps Institution of Oceanography, his career spans isotope geochemistry, mantle petrology, and meteorite studies. Phil curates UCT’s world-renowned Upper Mantle Research Collection, supporting global research into the deep Earth.

Dr. Sara Burness is a Lecturer jointly appointed between the Department of Geological Sciences and the Department of Chemical Engineering at UCT. Her research focuses on mineral processing, with a special emphasis on diamond breakage. She also investigates the origin of diamonds, mantle xenolith petrogenesis, and processes involved in lithospheric mantle modification. As a member of the Centre for Minerals Research (CMR), she plays a key role in bridging the gap between geologists and engineers.

Sinelethu Hashibi is a PhD candidate in mantle geochemistry and a Senior Scientific Officer at UCT. Her research focuses on the chemical and thermal structure of the lithospheric mantle, utilising the geochemistry of single kimberlite indicator minerals to understand the underlying mantle. She is also the lead translator for Chosi Ndabazomhlaba, a project aimed at communicating geoscience to Isi-Xhosa speaking communities through story-telling. 

Merrily Tau is a PhD candidate in mantle geochemistry at UCT. His research focuses on using olivine as a diamond indicator mineral to assess the depth of mantle sampling by kimberlites. He is also involved in mantle xenocryst studies, contributing to understanding the chemical and thermal structure of the lithospheric mantle. Merrily was recognised for his science communication efforts, winning third place in the 2024 CIMERA Science Writing Competition for his piece "Finding a Needle in a Haystack."

Ellwin Shiimi is a PhD student at UCT researching kimberlitic megacrysts from the Camp Alpha kimberlites in Liberia. His work focuses on unraveling the formation, composition, and mantle processes recorded in these megacrysts, providing new insights into the deep Earth and kimberlite magmatism in West Africa.

Fillsmith Ndongani is a PhD student at UCT investigating kimberlite indicator minerals from the DRC and Angola. His research aims to constrain the composition of the lithospheric mantle and assess its diamond potential, shedding light on the geological processes that control diamond formation and preservation in central Africa.

Anele Joni is an MSc student at UCT whose research investigates the origin of corundum xenocrysts from the Kareevlei olivine lamproite on the Kaapvaal Craton. His work aims to determine their genesis and explore potential links to subducted crustal material stored in the lithospheric mantle.

Michelle Brits is an MSc student at UCT researching the morphology and etch features of diamonds from the Roberts Victor lamproite. Her work aims to compare these characteristics with those of diamonds from kimberlites. This project is conducted in collaboration with Prof. Yana Fedortchouk from Dalhousie University, where Michelle recently visited to work in Prof. Fedortchouk’s laboratory.

Sihle Gqoboka is an MSc student at UCT investigating the morphology and etch features of diamonds from the Helam mine, which exploits the Swartruggens olivine lamproite dikes. In collaboration with Prof. Yana Fedortchouk from Dalhousie University, his research explores the growth history and surface alteration of these diamonds. His project also draws on the extensive UCT diamond collection to enhance comparative analysis with diamonds from other sources.

Nikita Erasmus is an MSc student at UCT studying Karoo-aged basalts from the Nyamandlovu region in Zimbabwe. Her geochemistry research focuses on melt interactions with the sub-continental lithospheric mantle (SCLM) during the generation of continental flood basalts. The project aims to classify these basalts and compare them with other Karoo basalt remnants across southern Africa to better understand regional mantle processes.

Khethukuthula Ndebele is an MSc student at UCT studying kimberlitic megacrysts from the Premier kimberlite. His research aims to understand the complex melt–sub-continental lithospheric mantle (SCLM) processes occurring at the base of the lithosphere, shedding light on mantle dynamics and kimberlite genesis.

Bokani Moyo is an MSc student in the Department of Chemical Engineering at UCT and a member of the Centre for Minerals Research (CMR). His research focuses on diamond breakage, specifically studying diamonds from the Roberts Victor mine to understand how they break during recovery processes.

Teboho Nkotsi is a geologist currently working at the Letseng mine while pursuing an MSc at UCT. His research focuses on mantle xenoliths and indicator minerals from on- and off-craton locations around the southeastern margin of the Kaapvaal Craton, aiming to better understand mantle composition and diamond potential in this region.

Anele Msomi is an MSc student at UCT studying diamond breakage of diamonds from the Helam mine. His research aims to understand how diamonds break both during transport in the kimberlite magma to the surface and during recovery processing, providing insights to improve diamond preservation.

Keletso Letsoko is a BSc Honours student at UCT conducting research on the olivine chemistry of the Karowe North and South pipes. Using samples from the Mantle Room collection, her project aims to constrain kimberlite petrogenesis and explore possible links to diamond grade.

Lephuting Phate is a BSc Honours student at UCT conducting research on the olivine chemistry of kimberlites from the Lulo kimberlite field. Using samples from this region, his project aims to constrain kimberlite petrogenesis and explore links to diamond grade. This work is carried out in collaboration with Lucapa Diamonds.

Affectionate Makamu is a BSc Honours student at UCT conducting a geochemistry project on kimberlites from Lesotho. His research aims to better understand the petrogenesis of these kimberlites and their implications for mantle processes.

Kabelo Nxumalo is a BSc Honours student at UCT conducting research on the olivine chemistry of kimberlites from Tsabong, Botswana. His project focuses on constraining kimberlite petrogenesis and investigating potential links to diamond grade using samples from this region.