Gd. Mcorist et al., TRACE-ELEMENTS IN AUSTRALIAN OPALS USING NEUTRON-ACTIVATION ANALYSIS, Journal of radioanalytical and nuclear chemistry, 185(2), 1994, pp. 293-303
Neutron activation analysis was used to determine the concentration of
trace elements in 42 samples of black, grey and white opals taken fro
m a number of recognised Australian field. The results were evaluated
to determine if a relationship existed between trace element content a
nd opal colour.