Stone balls on a beachSourced
The rounded boulders began inside seafloor mud
New Zealand’s Moeraki Boulders are large, rounded concretions. Minerals cemented marine mud into these masses, which coastal erosion later exposed from the surrounding rock. Their shapes were not carved by people.
The beach’s stone balls began beneath an ancient sea.
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Moeraki Boulders · Wikimedia contributors
Adapted, summarized and translated from the source. Adapted text is also available under CC BY-SA 4.0.
Reviewed: 2026-10-10