NONDESTRUCTIVE NEUTRON-DIFFRACTION ANALYSIS OF STS 5 (AUSTRALOPITHECUS AFRICANUS) AND OTHER FOSSILS FROM STERKFONTEIN, SOUTH-AFRICA

Neutron diffraction analysis (NDA) is inherently a non-destructive tec hnique(1) which can be applied to determine chemical phase composition , micro-structure, as well as grain preferred orientation (texture) pr ofiles in bulky samples. Exploratory NDA tests at the SAFARI-I nuclear reactor at Pelindaba, near Pretoria, were undertaken initially on non -hominid (alcelaphine) teeth, powdered wildebeest tooth enamel, synthe tic hydroxyapatite, calcite and associated breccia from Sterkfontein, to test the feasibility of the technique in general. Investigations we re extended to include the most complete cranium of Sts 5 'Mrs Ples' ( Australopithecus africanus), discovered in 1947 by Broom(2-5) at Sterk fontein and dated to approximately 2.5 million years of age.