Rietveld X-ray diffraction and X-ray fluorescence analysis of Australian aboriginal ochres

Rietveld phase analysis of X-ray powder diffraction patterns and chemical analysis by X-ray fluorescence spectroscopy have been used to characterize a series of red and yellow ochre samples from Aboriginal ochre deposits in South and Western Australia. The ochres were found to have diverse mineralogy, being mixtures of up to seven minerals, and also to have complex trace element signatures. The mineralogical characteristics and geochemistry of the ochres can be used to identify the source quarries. Using this combination of analytical techniques it may be possible to trace the source of ochres in burial sites and on objects back to the original quarries.