Paper valentines spanning three centuries of optimism about romance have been delivered to the Huntington Library, Art Collections and Botanical Gardens in San Marino, California.

The collection of about 12,000 cards was assembled over four decades by Nancy Rosin, a historian and collector in Franklin Lakes, New Jersey, whose family has donated it to the museum.

Rosin spent up to thousands of dollars each for the valentines, which were produced as early as the 1680s.

Their motifs, aside from the expected hearts and Cupids, can seem unsentimental. Images of battlefield tents represented spaces where soldiers could carve out time to write to their sweethearts, and depictions of caged mice may symbolize a desire to keep beloveds captive.

“Love was expressed in so many ways,” said Rosin, who also helps catalog valentines at the Metropolitan Museum of Art in New York.

Inscriptions and names on the cards and envelopes sometimes make it possible to determine which correspondents ended up happily married and which broke up, said Rosin.

In some cases, she added, women would reject men who had spent too much money on elaborate valentines.