The Devils Marbles formations began when molten volcanic granite cooled quickly. The cooling rock formed
a lattice with regularly spaced hairline cracks in the granite forming large, often very regular, blocks
of rock fitting together like exquisite masonry. Over millions of years water and wind have eroded
the rock surfaces exposed by the cracks. The result is the pile of 'Marbles'.
The oxidation
of iron ores within the granite provides the colour. Flaking off a piece of 'marble' reveals typically
grey-flecked granite.
