A high-strength and high-toughness nacreous structure in a deep-sea Nautilus shell: Critical role of platelet geometry and organic matrix

To explore the differences in mechanical behavior of nacre between shells that live in different water depths, the microstructures, phase composition and related mechanical properties of nacre under indentation, three-point bending and shear tests in deep-sea Nautilus and freshwater Cristaria plicata shells were systematically investigated. It is found that the nacreous structure in Nautilus shell exhibits an outstanding combination of high...