Hand of Glory has dated this piece to the 19th Century.

The panel is dated 1928 bottom right front, the reverse bears two dates one for 1930 and a restoration date for 1965 but the panel does look to be late 19th Century.
43cm x 29.5cm including frame
Saint Helena also known as Saint Helen, Helena Augusta or Helena of Constantinople (ca. 246/50 – 18 August 330) was the consort of Emperor Constantius, and the mother of Emperor Constantine the Great. She is traditionally credited with finding the relics of the True Cross, with which she is invariably represented in Christian iconography. (ref. Wikipedia)
Hand of Glory has dated this piece to the 19th Century.
Decorative antiques & interiors
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