Gellert Grindelwald's pendant

This vial possesed the sealed blood of Albus Dumbledore and Gellert Grindelwald after their blood pact. The vial was in Grindelwald's possession for many years. However, during the Battle in the Lestrange Mausoleum at the Père Lachaise Cemetery in Paris, France in September 1927, the vial was stolen without Grindelwald's knowledge by a Niffler belonging to Newt Scamander. Scamander subsequently brought the vial to Dumbledore at Hogwarts shortly thereafter, so he could attempt to destroy it, but it was impossible.