What unique 14 sacred items were made in Australia by the Original Australians and were all found together at the side of a sand dune that had been weathered away?

These were 14 rocks, determined to be a cache of sacred etched rocks and artifacts of the Original people of Australia long before Cook ever discovered the land. Each holds etchings that, in addition to varying sizes, make each rock unique. They were all found grouped together, signifying their importance.