Researchers discover mother-of-pearl production process

ITHACA, N.Y., Dec. 7 (UPI) -- Researchers at Cornell University have uncovered the process by which mollusks make nacre, also known as "mother of pearl."

Materials scientists say they can use their new understanding to synthesize mother of pearl in the lab, a substance with impressive hardness and durability.

"We have all these high-tech facilities to make new materials, but just take a walk along the beach and see what's being made," Robert Hovden, a postdoctoral research associate at Cornell, said in a press release. "Nature is doing incredible nanoscience, and we need to dig into it."

Hovden and his colleagues were able to gain a glimpse of the inner workings of a fan mussel (Pinna nobilis) by slicing and sanding down a thin cross section of shell. Scientists next embedded tiny diamonds in the shell and imaged the nacre production process using a high-resolution scanning transmission electron microscope (STEM).

As the scan revealed, the mussel created mother of pearl by slowly depositing layers of a material featuring calcium carbonate nanoparticles. These particles move from the inside to the outside of each layer, fusing together to form flat crystals. Each layer of crystal is sandwiched by thin films of organic material.

Mother of pearl get its iridescence, its beautiful rainbow-like sheen, because the layers are thinner than the wavelengths of visible light -- thus scattering white light as it hits the material.

The discovery was described last week in the journal Nature Communications.