I have a silver medallion awarded to Monsieur William de Lignemare (Following his name it reads "Temoignage de Reconnaissance 1924 "), sourrounded by oakleaves. It was Presented by, Societe Centrale de Sauvetage des Naufrages. It's larger and heavier then a silver dollar. On the flip side is a depiction of a ship going down during a storm with sailers in the water and clinging to the ships mast, being rescued by men in a life raft. I have no idea what this is and would appreciate any information you can offer.