Skippings Fine Arts has dated this piece to the 1960s.
I am however rather inclined to trust the genealogical information I unearthed, which records her birth in 1913.

The daughter of a Duke who was an amateur portrait painter, Alexandrine initially studied art history at the Ecole du Louvre, and subsequently at the Académie Julien and de la Grande Chaumière, where she was taught by the cubist master André Lhote. She also worked with Yves Brayer and Lucien Simon. Her career as an artist was suspended during the war, when she worked as a nurse for the Red Cross to help the war effort. She had her first solo show in Paris in 1948: more than twenty further ones would follow, in France, the US and Central America.

An independent woman, who nearly abstained from marriage to focus on her vocation as an artist Alexandrine moved to Mexico in 1951 In Mexico City, she took advanced classes at “La Esmeralda”, the National School of Painting, Sculpture and Printmaking.

while continuing to exhibit at the Paris Salons. Works by the Alexandrine are in the collections of the The National Institute of Fine Arts in Mexico; The Houstonian in Houston, the International Association of Plastic Artists, Tlaxcala, the Museum of Monterrey, and the Museum of Tel Aviv. Our painting by Alexandrine dates from circa 1960, and comes from a French collection. An oil on canvas board measuring 17 x 27 cm, the artwork is signed at the lower left. The overall framed size in a period frame is 29 x 39 cm.
Skippings Fine Arts has dated this piece to the 1960s.
Modern french & continental pictures selected by a former french auction house expert
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