Photographer Nicholas Cullen captured images of a rare jade iceberg in the Southern Ocean off the east coast of Antarctica. Jade icebergs form when seawater containing algae freezes on the bottom of a glacier. [Photo: IC]"

Photographer Nicholas Cullen captured images of a rare jade iceberg in the Southern Ocean off the east coast of Antarctica. Jade icebergs form when seawater containing algae freezes on the bottom of a glacier. [Photo: IC]"

Photographer Nicholas Cullen captured images of a rare jade iceberg in the Southern Ocean off the east coast of Antarctica. Jade icebergs form when seawater containing algae freezes on the bottom of a glacier. [Photo: IC]"

Photographer Nicholas Cullen captured images of a rare jade iceberg in the Southern Ocean off the east coast of Antarctica. Jade icebergs form when seawater containing algae freezes on the bottom of a glacier. [Photo: IC]"