It’s extraordinary that the casts — easily broken and never meant to be moved from place to place — survived at all. When the Met opened in 1872, it did not possess the renowned collection of ancient art it has today. Fortunately, there was no stigma attached to copies. A booming reproduction business in Europe churned out plaster casts that people on grand tours could take home as souvenirs. Museums in the United States, where curators never dreamed of ever owning their own original Classical art in marble, gobbled them up, too, giving their visitors a taste of the glories of Greece and Rome.

From 1883 to 1895, the Met assembled a plaster collection that went well beyond run-of-the-mill copies. It acquired casts of architectural elements from the Parthenon and the Erechtheion and scale models of the Pantheon and the Cathedral of Notre Dame. Under the eye of a committee that included Augustus Saint-Gaudens, Louis Comfort Tiffany and Stanford White, the Met obtained permission from museums in Europe to take the first-ever castings of figural works by Donatello and other Renaissance sculptors. The collection, installed in what is now the Medieval Hall and its adjacent wings, eventually numbered over 2,600 pieces.