From: Thyssen-Bornemisza 

"The present painting is an autograph copy of the painting entitled The Honorable Mrs Charles Russell, painted by Sargent  in 1900 and now in a Californian private collection. In 1889 the sitter, great-grand-daughter of one of the founders of the London Daily News, had married the leading lawyer Sir Charles Russell, famous for winning the case against Oscar Wilde which led to the poet's imprisonment.

"The mysterious and rather nervy face of Mrs Russell is characteristic of Sargent's elegant female portraits. The palette of ochres, silvers and pale pink is rather sober, while the rapid brushstroke is a characteristic example of Sargent's great skill and refinement."
(Thyssen-Bornemisza website)
 

Notes: 

• See the years in review 1900
• See the Thyssen-Bornemisza website (there is an english page as well)
• See Are there more paintings of Mrs Charles Russell?

Special thanks go to Cristina,  <xinabonita@mixmail.com> for telling me about four paintings held at the Thyssen-Bornemiseza museum.