Pair of Italian Mid-Century Modern Reverse Glass Paintings of Royalty

A pair of unusual and very intriguing large scale reverse glass paintings of a noble man and woman. She with her long neck and limbs, dressed in an elegant gown metallic copper gown. He in a handsome waistcoat and chapeau holding a cane, with a sword tucked in his belt. Each with a stylized fleur de lis.
Impressive in scale at 33 inches high by 23 wide, the technique of using metallic colors set against an iridescent white background is fascinating, something I have never seen. Though the figures appear to be depictions of French nobility, these are most likely Venetian in origin.