One of the earliest pieces from PabloPicasso's iconic Blue Period has revealed an unexpected discovery: another figure beneath the surface. This finding provides further insight into the process of the painter's work during this pivotal time in his life.

Three things to know:

1. The 1901 painting titled "Portrait of Mateu Fernández de Soto" portrays the eponymously named sculptor, a friend of the young Picasso. At just 19 years old, Picasso had recently arrived in Paris for his first exhibition in the city.
   
2. According to the Courtald Gallery in London, which houses the painting, advanced X-ray and infrared imaging technology uncovered a portrait of a woman beneath the image of Soto. Experts estimate this underlying portrait was created a few months before the final piece.
   
3. There are several theories for the presence of this unidentified woman hidden beneath the surface for more than a century. One possibility is Picasso's financial need to reuse canvases during that time. Additionally, he was known to layer his works instead of whitewashing a canvas to start fresh.

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So, who is this gal?

As for the identity of this woman, further research may eventually shed light on who she is. Museum curators currently have no definitive answers, but they speculate that she could have been a model, a friend, or possibly even a lover who posed for Picasso.

Her posture and style resemble those found in several other works depicting seated women that Picasso created in the same year. Researchers theorize there might even be more layers hidden beneath her image.

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• For more on art, read about why Mona Lisa's roommates may be glad she's finally moving out.
  
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