It all started with a black-and-white photograph of a painting.

Lola Álvarez Bravo, a photographer who captured the painter’s early works, took an image of Frida Kahlo’s self-portrait Niña con collar (Girl with Necklace). The 1929 oil-on-canvas ended up a part of the artist’s catalogue raisonné, but little was known about the origins of the work.

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Decades later, according to Sotheby’s, which is offering it in its November 22 Latin America: Modern Art sale, its whereabouts remained unknown.

In 1955, the year following the artist’s death, Kahlo’s husband Diego Rivera gifted the painting to a woman who had assisted his late wife in her studio, according to Reuters. Since then, Niña con collar has maintained a lengthy absence from the public eye, hanging inside a home in Sunnyvale, California. The well-preserved work now approaches its sale date with an estimate of $1.5–2 million.

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The elusive work features a seated woman wearing a striking orange shirt and green shawl, complemented by gold hoop earrings and a beaded necklace.

A visitor looks at “Portrait of a Lady in White” at the Frida Kahlo Retrospective at Martin-Gropius-Bau on April 29, 2010 in Berlin. Courtesy of Sean Gallup/Getty Images.

It is a “beautiful and warm painting,” says Axel Stein, the head of Latin American art at Sotheby’s, in a statement.

Although it lacks the spatial depth and adornment present in her later works, this rediscovered painting is an evident precursor to Kahlo’s better known portraits, which depict compelling, serious women and girls with direct gazes.

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