36 Calcium carbonate chaos

The sand of Raja Ampat (Indonesia) is a happy mix of shapes. Here, foraminifera, spines of sponges, sea urchins and soft corals, shells of snails, mussels, bryozoans, brachiopods and coccolithophores, stems of crinoids and much more can be found in a tiny sample. This rectangle has a diagonal of about eight millimetres.

Calcifying organisms are not just fascinating to look at but they also help the ocean to maintain its function as a carbon dioxide sink and to mitigate the effects of global climate change.

Photo: Solvin Zankl