Moeraki Boulders

The Moeraki Boulders are a number of huge spherical stones, found strewn along a stretch of Koekohe Beach near Moeraki, a small settlement just south of Hampden on New Zealand's Otago coast.

These boulders are grey-coloured septarian concretions which have been exposed through shoreline erosion from black mudstone coastal cliffs that back the beach.
They originally formed in ancient sea floor sediments during the early Paleocene some 60 million years ago.

The boulders weigh several tons and are up to three metres in diameter.