Roy Precious - Antiques & Fine Art has dated this piece to the 18th Century.
Signed and dated 1730, lower left, partially obscured by the later inscription 'Mr. Grenaway'.

This is a particularly fine, sensitive and insightful portrait and ranks among Heins very best work.

William's portrait, also on this website, is the same size and framed to match, but this lady looks considerably older than him, she wears widow's weeds [1], and is depicted looking in the same direction as him. When hanging together, one of these portraits would have its back to the other. As a general rule, husband and wife portraits depict them inclining towards each other, not away.

[1]The “weeds” in the term comes from the Old English waed, which means “garment.” Widow's weeds have several defining characteristics, including dark or muted colours and simple designs.
The wearing of widow's weeds would have instantly distinguished a widow from those around her, making her state very obvious. It was also a class symbol, as only the very wealthy could afford the mourning ritual of full mourning to half mourning etc, which involved an entirely new wardrobe and a general withdrawal from society.

JOHN THEODORE HEINS (1697-1756), also known as Dietrich or Dirk, was born in Germany. He settled in Norwich (at that time a city second in importance only to London) in 1720.
He made a good living painting the local prosperous merchants and gentry and was accepted into their social circle. His style was influenced by that of Thomas Hudson.
Many of his finer works were commissioned by the Astley family of Melton Constable.
Heins died in Norwich and his will was proved 30 August 1756 by his widow, Abigail.
His son, also called John Theodore Heins was also a portraitist but lacked his father's talent.
Heins senior's work is in Norwich Castle Museum, Felbrigg Hall (National Trust), the National Portrait Gallery, Cambridge University and others.
SIZE: 34.5 x 29.5 inches including the frame.
PROVENANCE: Old collection, a Norfolk country house.
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.
You can view the stock and full dealer information on the Roy Precious - Antiques & Fine Art Profile Page