Ravenclaw Diadem

Rowena Ravenclaw's Diadem

Rowena Ravenclaw's Diadem, which is also known as the Lost Diadem, was the only known relic that once belonged to Rowena Ravenclaw, the founder of Ravenclaw house at Hogwarts School of Witchcraft and Wizardry. Etched upon its surface was Ravenclaw's famous quotation: "Wit beyond measure is man's greatest treasure." It was said to enhance the wisdom of its wearer, which is Ravenclaw House's most treasured attribute. The diadem was later stolen by her daughter, Helena, a fact Rowena kept a secret from the other founders till her death bed.

Rowena Ravenclaw's Diadem, Helga Hufflepuff's Cup, and Salazar Slytherin's Locket, made up three of Lord Voldemort's seven Horcruxes.