Late 18th century English playing set

A magnificent set from the late 18th century, with kings standing just over 5.1" tall, weighing in at 56g.

Open crownwork, with a ball finial expertly carved within the crown.  The set must surely be from the same workshop as a set in the Jon Crumiller collection. Jon's set is in red and white (natural), whereas this one is in black and white (natural) - I had wondered whether the black was a later staining, but it is indeed original to the set, as evidenced by the wear pattern and the lack of any other colour on the threads when unscrewed.   The black has faded into a wonderful chocolate and coffee patina.

One slight oddity with the set is the white queen's finial.  At first I thought the black queen was the odd one, but that one matches Jon's set and is original.  The white queen's cross finial is a perfect fit, and size-wise it is identical to the king's finial.  It's a bit of a mystery - I can only think that it was originally fitted like this (perhaps the buyer wished to distinguish the queen), or replaced not long after manufacture (customer: "I've broken my finial, can I have a replacement please"; workshop: "they *must* mean the king's finial, as that is most likely broken.  We'll send one by errand boy tout suite"; customer, too embarrased to return the cross, fits it and lives with it).