Australian pottery mark- R in a diamond - Bali?

Hi there, any help to identify this pottery would be appreciated. I have acquired a collection and would love to know the artist. Impressed capital R inside a diamond shape.

A lot of similar ones with green or blue glaze and applied lizards and frogs are made in Vietnam and Bali

I would agree with Naomi. The fancy stuff on those pieces, the grapes and leaves, and the frogs? and leaves are moulded pieces applied on top of the bowl. Not something any studio potter who practices as an individual would really ever do. It would be entirely against the ethos of studio pottery, as the very process of indicates mass production