The right answers are: refined petroleum, coal and diamonds. Australia is rich in natural resources. The most outstanding, in terms of commercial value, are bauxite, bituminous COAL, iron ore, nickel, gold, lead, zinc, silver, REFINED OIL, and natural gas extracted from the coasts.
The huge DIAMOND deposits discovered in the Kimberley in 1979 have made Australia one of the world´s leading suppliers in terms of volume and sixth in terms of value.