Faculty of Natural and Agricultural Sciences
School of Physical Sciences
Department of Chemistry
Vibrational Spectroscopy and Materials Chemistry
Research focuses on the utilisation of vibrational spectroscopy to investigate materials of importance for art and archaeology. This includes the synthesis and reactions of inorganic pigments and other materials that can shed light on the nature and origin of these materials. For instance, the blue pigment, used for the decoration of Chinese blue and white porcelain-ware from the Ming-dynasty (1368 - 1644), was investigated using Raman spectroscopy. The shards on which the recordings were made, came from 16th and 17th century Portuguese shipwrecks around the South African coast. The Raman spectrum of the pigment was not available in existing Raman databases and the cobalt blue pigment had to be prepared by high temperature synthesis in this laboratory before it could be identified as the spinel CoAl2O4 or cobalt aluminate that was first synthesised in the western world during the 18th century. Similar investigations were undertaken for carotenoid pigments on molluscan sea shells, ceramic shards from South African archaeological sites such as Rooiwal, Makahane, Lydenburg and Graskop. Comparisons are made between local samples and ones that originated from Europe or Asia. The preparation and properties of some of the related pigments are being investigated on the nanoscale since particle size is an important parameter in pigment quality
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