The sea silk fabric shines like spun gold, and it is said that it may have inspired the legend of the Golden Fleece in Greek mythology. This silk is derived from the byssus fiber of the giant Mediterranean clam (Pinna nobilis), but due to the endangered species, the traditional craft is at risk of being lost. Now, scientists at Pohang University of Science and Technology in South Korea have successfully recreated this legendary fabric by recycling discarded byssus from the edible clam (Atrina pectinata) and revealed the molecular mechanism behind its golden luster. Relevant research was published in Advanced Materials.
The production of traditional sea silk can be traced back to the second century AD. The process includes collection, seawater washing, freshwater desalination, drying and carding, and then soaking in lemon juice to enhance the luster. However, with the Mediterranean giant clam being listed as a protected species by the European Union, this source of raw materials has been cut off.
The research team found that the byssal threads of Korean edible clams are highly similar to the fiber properties of endangered species, and that their byssus threads are usually discarded as waste. By replicating traditional craftsmanship, the team successfully spun golden silk from edible clams that is almost the same as original sea silk. Researchers from the Museum of Natural History in Basel, Switzerland, pointed out that this discovery has long been confirmed by folk practice, and Italian weavers have independently tried similar methods.
Further research found that the golden luster of sea silk comes from its unique globular protein structure, rather than the linear protein of traditional animal fibers. These proteins self-assemble into bundles of nanofibers, which produce iridescence through light interference effects. Citric acid treatment can remove the iron ions in the byssus, making the golden color appear. This pigment is extremely stable and can last for thousands of years without fading.
This research not only provides an alternative for reviving the sea silk craft, but may also promote the application of non-toxic golden pigments in textiles, cosmetics and other fields.