One thing's for sure...it's blue.

Tiny pot, 6cm diameter. It has a scratched double 'M' on the side (photo) as well as possibly another sprigged mark to the top which is obscured by glaze but might be another 'M'. I thought Marcio Mattos? Other pieces by him are only similar in that they are blue, though. Thanks for any suggestions.

I have one piece of his work in my own collection and it has both the impressed M seal (on the side) and the incised wavy double M signature (on the base). It is a teabowl form so not typical of his slab built forms but your little pot isn't like anything by him that I've seen.