Mother of Pearl Polished Decorative Shells
Nacre, also known as Mother of Pearl, is an organic-inorganic composite material produced by some mollusks as an inner shell layer; it is also what makes up pearls. It is very strong, resilient, and iridescent.
Nacre is composed of hexagonal platelets of aragonite (a form of calcium carbonate) 10-20 µm wide and 0.5 µm thick arranged in a continuous parallel lamina. These layers are separated by sheets of organic matrix composed of elastic biopolymers (such as chitin, lustrin and silk-like proteins). This mixture of brittle platelets and the thin layers of elastic biopolymers makes the material strong and resilient, with a Young's modulus of 70 GPa. Strength and resilience are also likely to be due to adhesion by the "brickwork" arrangement of the platelets, which inhibits spreading of transverse cracks. This design at multiple length sizes increases its toughness, making it similar to that of silicon.
Nacre is secreted by the epithelial cells of the mantle tissue of various molluscs. The nacre is continuously deposited onto the inner surface of the shell, the iridescent nacreous layer, commonly known as mother of pearl. The layers of nacre smooth the shell surface and help defend the soft tissues against parasites and damaging debris by entombing them in successive layers of nacre, forming either a blister pearl attached to the interior of the shell, or a free pearl within the mantle tissues. The process is called encystation and it continues as long as the mollusk lives.
Currently the chief sources of mother of pearl are the pearl oyster, freshwater pearl mussels, and to a lesser extent, abalones. Mother of pearl have been used to make buttons especially during the 1900s.
Gold Mother of Pearl Plate
- One Polished Gold Mother of Pearl Plate 8 to 5/14 inch..... $12.49
One Polished Gold Mother of Pearl Plate 5 1/2 inch...... OUT OF STOCK
Silver Mother of Pearl
- One Polished Silver Mother of Pearl 2 to 2 3/4 inch..... $2.10
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