Tough as conch

A review of the literature by Cambridge chemist reveals that the nanoscopic structure of conch shells might be used as a model for creating composite materials as tough as steel but much less dense and perhaps far less costly to make in terms of energy and expense. The team discusses how the shell of the queen conch despite being little more than calcium carbonate and some organic matter is formed from nanoscopic single crystals in a cross-layered 3D structure that makes it as tough as mild steel pound for pound. This nanocrystalline structure prevents cracks from propagating through the shell. However, to make a truly biomimetic material, researchers will not only have to find a way to copy this structure they will also have to develop technology to heal any tiny cracks that form, something the living sea snail does with little effort in its battle against turtle jaws and crab claws.