One of the biggest price tags at this year’s Art Basel Miami Beach is attached to one of its smallest works. A Frida Kahlo self-portrait measuring 5cm tall is being shown on the stand of Weinstein gallery from San Francisco. Autorretrato en miniatura (miniature self-portrait, around 1938) is the only mini of the 55 known self-portraits by the artist.

The pocket-sized self-portrait is on sale for $15m, a sharp mark up since Weinstein bought it from Sotheby’s New York in 2011, shortly after it failed to sell at an auction for its $800,000 to $1.2m estimate. The work had previously sold at auction in 2000, also at Sotheby’s New York, for $225,750. Kahlo’s market has risen tremendously in recent years and broke the record for a woman artist at auction last month, with the $54.7m sale of El sueño (La cama) (the dream, the bed, 1940) at Sotheby’s New York.

While the front of the canvas shows the artist sporting her recognisable updo of red flowers and braids, the reverse reveals a more intimate story. Inscribed “Para Bartoli con amor, Mara” (to Bartoli with love, Mara), it is dedicated to one of Kahlo’s lovers, the Catalan poet José Bartoli, with whom she had a passionate affair during the final decade of her life.

“Kahlo wrote to Bartoli that she painted this work small enough that he could carry her around in his pocket,” says Weinstein’s founder, Rowland Weinstein. She signed the painting “Mara”, a shortened form of Bartoli’s name for her, “maravillosa” (marvellous), to avoid detection from her husband, the artist Diego Rivera.

Kahlo is one of several female Surrealists whose prices are quickly rising to match their male counterparts amid a widespread reappraisal of their canonical importance. Works by some of these artists, such as Leonora Carrington and Leonor Fini, are also on Weinstein’s stand. “The only reason I can have a booth like this is because I began buying 25 years ago,” Weinstein says.

Kahlo’s paintings are hard to come by at art fairs: only around 150 of them are known to exist, with many in public collections. Weinstein believes this is the first time a painting by the artist has shown at Art Basel Miami Beach.

The miniature Kahlo painting remains unsold as of this writing. It is exhibited alongside two of her drawings, made when she was bedridden following surgery, both priced at $950,000.