"I hope this exhibition will confirm that they really were peers," Jones said. "They were colleagues, and it was a level playing field between them. He might have had more experience, but she was a fast learner."
Degas' influence on Cassatt is widely known in the art world, but Cassatt's role in shaping Degas' work has been more of a mystery. The best example is in their experimentation with metallic pigments and different materials, Jones said.
Degas saw Cassatt introduce gold or bronze materials into her paintings and decided to try it himself for his "Portrait After a Costume Ball (Portrait of Mme Dietz-Monnin)."
"I think it's just a fantastic back and forth," said Hoenigswald.
It was a moment of intense collaboration and experimentation around 1879 for the two artists, and then they moved on to other pursuits, Jones said.
Later Cassatt would write to American collectors about how only those with the most discriminating taste would appreciate works by her and Degas — a subtle marketing of the impressionists.
"Degas/Cassatt" will be on view in Washington through Oct. 5.
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