The last pope to be crowned with the tiara was Paul VI in 1963. I found this story quite interesting in that the workshop, where the tiara was crafted, specializes in making Orthodox vestments and mitres. More than likely the workmen were Orthodox because the company is located in heavily Orthodox Sophia, Bulgaria.
“Receive the tiara adorned with three crowns and know that thou art Father of Princes and Kings, Ruler of the World, Vicar of Our Savior Jesus Christ on earth, to whom is honor and glory in the ages of ages.”
CNA reports: Dieter Philippi, the man behind the project had these words to say about a coronation: “I think nowadays it would be very difficult because people wouldn’t understand the symbolism of a coronation … But from my personal view I would be very happy if we had a Pope who was crowned again like a king or a queen of any other country, yes.” Read full story here.