The Marsoulas Conch Shell (IMAGE) CNRS Caption At 31 cm in height, 18 cm in diameter (at the widest point) and up to 0.8 cm thick, this conch, which bears witness to a colder sea, is thus larger and thicker than more recent ones. Credit © Carole Fritz et al. 2021. Usage Restrictions May only be used for articles on this research. Please use full credit line. 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.