Paul VI did away with much of the regal splendor of the papacy. He was the last pope to date to be crowned; his successor Pope John Paul I replaced the Papal Coronation (which Paul had already substantially modified, but which he left mandatory in his 1975 apostolic constitution Romano Pontifici Eligendo) with a Papal Inauguration. Paul VI donated his own Papal Tiara, a gift from his former Archdiocese of Milan, to the Basilica of the National Shrine of the Immaculate Conception in Washington, DC (where it is on permanent display in the Crypt) as a gift to American Catholics.

What did Paul VI donate to the Basilica of the National Shrine of the Immaculate Conception ?