Masterpiece

A masterpiece was a work of art that was considered to be a supreme artistic achievement or the greatest work of an artist's career.

Spock said to Flint, "Your collection of Leonardo da Vinci masterpieces, Mister Flint, they appear to have been recently painted on contemporary canvas with contemporary materials. And on your piano, a waltz by Johannes Brahms, an unknown work in manuscript, written in modern ink. Yet absolutely authentic, as are your paintings." (TOS: "Requiem for Methuselah")

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