Omekodel Cave was littered with bones, some buried deep in the sandy floor; others lodged loose by waves and piled like driftwood. More, including several skulls like the water-worn one pictured here, were cemented to the cave in layers of calcite.

Calcite is created as water drips through limestone. Though it can form quickly, the mineral was found covering even the oldest bones in Omekodel, which date to 2,300 years ago. Bones in another cave, Ucheliungs, are up to 2,900 years old.

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