were obtained from a local mining site (Uley, Eyre Peninsula, South
Australia, Australia), crushed into powder using a benchtop ring mill
(Rocklabs), and sifted using a 25 μm sieve. Potassium permanganate
(Sigma-Aldrich), 85% w/w phosphoric acid (Chem-Supply), 98% sulfuric
acid (Chem-Supply), 30% hydrogen peroxide (Chem-Supply), 36% hydrochloric
acid (Chem-Supply), 64–65% hydrazine monohydrate (Sigma-Aldrich),
30% ammonia (Chem-Supply), cysteamine hydrochloride (Sigma-Aldrich), N,N-dimethylforamide (DMF, Chem-Supply),
2,2-azobis-2-methylpropionitrile (AIBN, Sigma-Aldrich), hexane (Chem-Supply),
ethyl acetate (Chem-Supply), and ethanol (Chem-Supply) were used directly
without prior purification.