Reporting back as promised...
The good news is that it is a Michael Harris piece. Apparently he brought with him from Mdina a good stock of ingredients, hence the colour, and this piece was made in the early days at IOW.
The bad news is that it has a diagonal stress fracture and is only being held together by its base.
So there we have it. Mdina colours. IOW product. Made by Michael Harris. On its last legs. Hoorah!