Carved decoration vase with JG mark

Any ideas on this one? Can't find anything like it or on the "JG" mark. Appears to have a white base glaze covered in what looks like black or dark blue glaze, but which on close examination is more like very dark brown glaze which also shows shades of blue and green. The decoration is carved into the body and filled in a turquoise blue glaze. The mark appears to be hand produced rather than stamped. Size is H: 8 1/4"; D: 5 1/2". Appreciate any comments.

Would guess it's "Art Pottery" from the first half of the 20th century, not sure where from.

Thanks Potty - will have to continue the research.

The shape and glaze colours and geometric design reminds me of Safi pottery. I suspect it's Moroccan.

When I first caught sight of the vase out the corner of my eye I assumed it was N African/E Mediterranean and expected to find a more Islamic-style decoration. When I picked it up and saw the decoration and signature, they seemed British (or at least Western European).