Just how tough is it Physicist Pupa Gilbert at the Relojes audemars-piguet Réplica University of Wisconsin says that "You can go over it with a truck and not break it you will Relógios richard-mille Réplica crumble the outside of the shell but Relógios hublot Réplica not the nacre inside. And we dont understand how it forms thats why its so fun to study."