Artware Fineart has dated this Georgian Oil Portrait Painting to the 18th Century.
Portrait of an Elegant Lady
oil on canvas
10.1/2 x 8in. (26 x 20 cm.)
Her high-crowned, wide -brimmed hat with its large ribbon bow is particulalry fashionable for this period.

With thanks to Dr Susan North from the V and A for her help in identifying the clothing.
Francis Alleyne was a British portrait painter, usually on a small scale. He seems to have specialised in small, oval, three-quarter lengths, usually signed on the back, which look like middle class versions of Wheatley's more elegant small portraits.
Artware Fineart has dated this Georgian Oil Portrait Painting to the 18th Century.
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