The thorns of sea urchins, a model for better cement
The main component of sea urchin prunes (99%) is calcite, a very resistant and at the same time fragile material. However, the thorns of the sea urchins, being hard, have enough flexibility to withstand the blows.
Researcher Helmut Coelfen of the University of Constance (Germany), after studying the structure of calcite in the thorns of sea urchins, has discovered that calcite crystals are located in a lime group, such as bricks on the wall, and that between the crystals there are also proteins. It says it's amazing to see how nature turns a fragile material into a high-strength material.
The details of the study have not been made known, since an agreement has been signed with two major international companies to create hard and flexible cement.
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