Bio-mineral production uses less energy than ceramics

Inspiration for the materials comes from biological minerals of the sort found in seashells, which can rival ceramics in terms of hardness and mechanical properties but are created in aqueous environments at ambient temperatures.

‘With calcium carbonate, if it’s a pure geological sample you simply have to tap it with a hammer and it will fall apart along the cleavage planes,’ said Prof Fiona Meldrum of Leeds University. ‘But if you do this to a biogenic calcite crystal it fractures with extreme difficulty.’

The key feature of bio-minerals is that they are composites, made from an inorganic mineral such as calcium carbonate, with a small amount (often only 0.1 per cent by weight) of organic material, usually a protein.

‘You still have a perfect single crystal but inside this crystal you find these proteins. Quite how they are included in the structure isn’t well understood but it makes an enormous difference to the properties.’