Antique chess set (part 2)

Continued from part 1, showing more detail of the chess set.
The kings both have this device carved into the top, it may help with the origins.
The marble board squares have pink flecks in the black marble, and silver flecks in the white. Most unusual!
The knight piece can be seen to have great detail, and the wood has continuing flowing grain through the top and bottom.
Any help with age/origins would be great.
Thanks for looking, Bob.