Korean researchers have successfully recreated a rare and luxurious fiber once worn only by ancient emperors, using modern science and technology. A team led by Professor Hwang Dong-soo from the Departments of Environmental Engineering and Systems Biotechnology at Pohang University of Science and Technology (POSTECH), along with Professor Lee Gi-ra from Chemical Engineering and Professor Choi Ji-min from the Environmental Research Institute, has recreated the ancient fiber using farmed 'gaper clams' from local coasts. This replaces the now-protected Mediterranean clam that was originally used to make the silk.

Called “sea silk,” this rare material dates back to the Roman era and was once worn by only the most powerful figures, like emperors and popes. It was made using byssus, silky threads released by the Mediterranean clam Pinna nobilis to attach itself to rocks. Known for its golden glow, lightness, and strength, sea silk was often referred to as “legendary silk.”

To recreate sea silk, the researchers turned to gaper clams, which are commonly farmed and eaten in Korea. Like the Mediterranean clam, they also produce byssus to cling to surfaces. The team discovered that the byssus from these clams shares many similar features with the original, making it possible to process it in the same way as traditional sea silk.

Unlike fabrics dyed with chemicals, sea silk gets its color from a natural effect called “structural coloration.” This happens when tiny round proteins, known as 'photonin,' are layered in such a way that they reflect light uniquely, similar to the colors seen in soap bubbles or butterfly wings. Because the color comes from the fiber’s structure itself, it doesn’t fade over time.

They further found that the more organized these protein layers are, the brighter and clearer the color appears. This structured arrangement is what gives sea silk its remarkable stability against fading, even after thousands of years.