Roy Precious - Antiques & Fine Art has dated this piece to the 18th Century.
The sitter within a feigned stone oval.

Mary (1662-1694) was the elder daughter of James, Duke of York (later James II) and his first wife, Anne Hyde.
She was married to her cousin William III of Orange at the age of fifteen.
When her Catholic father James was ousted at the Revolution of 1688 the Protestant Mary and her husband returned to England from Holland and they were jointly crowned Mary II and William III in 1689.

The original of this portrait was painted at the time of her marriage in 1677. A number of versions of this portrait exist including one in the Royal Collection and one in the National Portrait Gallery.
The rich and daring colour scheme with its clashing orange and red testifies to Lely's skill as a colourist. The choice of orange, an unusual colour in Lely's portraits is perhaps a reference to Mary's new title, Princess of Orange.
SIR PETER LELY (1618 - 1680) was the most important portraitist in the reign of Charles ll, although he had painted portraits throughout the Commonwealth. Dutch born as Pieter van der Faes, he became Principal Painter to the King, painting everyone of importance and maintaining a busy and active Studio to help with the huge demand for his portraits.
IMPORTANT NOTE: This lovely little painting has, at some time in the past, been overcleaned and, as can be seen, the paint is now rather thin. Hence the very low price.
Despite this fault it is still a charming little portrait.
SIZE: 16 x 14.5 inches framed. Image size 13 x 10.5 inches.
PROVENANCE: Private Collection, Sussex.
Roy Precious - Antiques & Fine Art has dated this piece to the 18th Century.
Roy and nadine precious: specialists in portraiture from the 16th to the 20th century. Established in 1972.
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