Richard Grenfell THOMAS (1901-1974) was a mineralogist and biochemist and we’ve ‘rediscovered’ him because many rock and mineral samples he collected are housed in the Tate Museum in the Department of Earth Sciences at the University of Adelaide.
At age 18, in 1919, he joined the Herbert BASEDOW expedition to provide medical assistance to Aboriginal communities in outback South Australia and Queensland. While at the University he was a contemporary of and good friends with Mark OLIPHANT (nuclear physicist) and Reg SPRIGG (geologist). THOMAS graduated from the University in 1924, having completed a thesis entitled ‘A remarkable occurrence of monazite’1 under the supervision of Prof. Douglas MAWSON in our Department (then Geology & Mineralogy). For this, he was awarded the Tate Memorial Medal for ‘the best original work in Australasian geology embodied in a thesis’2 . He went on to do post-graduate work with MAWSON, and later joined the Australian Radiation Corporation to develop techniques for the extraction of U, Ra, Sc and V from Radium Hill ores.
THOMAS returned to the University in 1928 to work under Prof. Brailsford ROBERTSON in the Biochemistry Department which subsequently became CSIRO’s Division of Animal Nutrition. Here, THOMAS played an important role in the identification of ‘coast disease’, a wasting disease in sheep raised on the calcareous soils in near-coastal regions in southern and western Australia, and he suggested trace element deficiency, particularly of Co, as the likely cause.
In 1959, THOMAS moved to Melbourne to become Chief of the new CSIRO Division of Mineral Chemistry, from which he retired in 1961. His main research role was to do with non-metallic minerals and ceramics. However, a quirky claim to greater fame came in collaboration with a colleague, Joy BEAR, when they became interested in the smell of first rains on soil: this was initially called ‘argillaceous odour’ but he renamed it ‘petrichor’. Their work in identifying this smell was initially published in Nature3 in 1964 .
THOMAS died in 1974: his ashes were scattered over Mt Painter (near Arkaroola Wilderness Sanctuary in the northern Flinders Ranges) and a memorial plaque erected there by his friend, Reg SPRIGG.
 RG Thomas (1924). A monazite-bearing pegmatite near Normanville. Transactions of the Royal Society of South Australia, 48, 258-268 (+2 plates).  Sunday Mail, 13 December 1924.  Bear, IJ & Thomas, RG (1964). Nature of argillaceous odour. Nature, No. 4923, March 1964, 993-995.
Dr Tony Milnes, Earth Sciences, University of Adelaide