Biodegradable Mardi Gras Beads (IMAGE) Louisiana State University Caption Mardi gras beads and doubloons pictured here range from plastic on the left to biodegradable algae on the right. Credit LSU Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.