Chinese, Qianlong period.
Never seen anything like it anywhere else in the world. But here I have found them in two places already: Arte Antiga and Medeira e Almeida. Apparently, the pattern was developed specifically for the Portuguese (Brazilian?) market. (There are even lame knock-offs made today).
The Met of course has it (and keeps it in storage): see some here. Decent-looking reproductions of the Met pieces can be had here.