Faculty of Natural and Agricultural Sciences
School of Physical Sciences
Department of Geography, Geoinformatics and Meteorology
Selected Highlights from Research Findings
San rock art sites are found throughout southern Africa; unfortunately this unique heritage is rapidly being lost through natural weathering processes, which have been the focus of various studies conducted in the uKhahlamba Drakensberg Park since 1992. It has recently been shown that the ability of Raman spectroscopy to identify salts on rock faces on a micro, as well as nano scale, can make a contribution to these projects. In order to test the feasibility of undertaking on-site analyses, a small rock fragment with red and white pigments still attached, which had weathered off the rock face, was analysed with Raman spectroscopy under laboratory conditions, using a Dilor XY Raman instrument and a DeltaNu Inspector Raman portable instrument. A small sample of black pigment (< 1 mm2), collected from a badly deteriorated painting and a few relevant samples collected on site, were analysed as well. It was possible to identify most of the inorganic pigments and minerals detected with previous XRD and EDX measurements, as well as organic phases not detected in San rock art before. Animal fat was detected on the pigments and on the back of the rock fragment. The spectra quality makes successful on-site measurements a good prospect.
Contact person: Prof KI Meiklejohn.
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