Art Sleuths: How To I.D. a Master

When he saw the drawing in April, Sir Timothy Clifford recognized Michelangelo "at a glance." It took three months of scrutiny for scholars to verify that Clifford, director of the National Galleries of Scotland, had discovered America's first Michelangelo in 26 years when he stumbled upon it in the archives of New York City's Cooper-Hewitt National Design Museum. Clifford and his fellow art sleuths shared with TIME the clues that convinced them.

HELMETED RAMS They're just like the ones Michelangelo designed at the New Sacristy of San Lorenzo in Florence. The foliage flowing from the ram is also similar

CHERUBS Just like the angelic youngsters that sprinkle the Sistine Chapel. Here the candlestick rests on their arms — characteristic of the artist's playfulness

SASHES The two figures preparing an oxen sacrifice are wearing sashes — an odd detail also seen on the Sistine Chapel nudes and the slaves on Pope Julius II's tomb

FEET At the base are two lion's claws, similar to the ones on a Michelangelo work for the Duke of Urbino — a drawing of a serving dish for salt