There's a picture of a piece in this pattern in the 2004 Miller's guide (top right, p273). It is described there as being early '70's, by Michael Harris. I don't know if the date is right, but none of my bits in this pattern have dates. I don't have a bit in yours' size and shape, Max.....:mrgreen:
I do quite like the pattern, but would agree with Paul that it's not quite pulegoso. The bubbles are too big, and the surface is not all rough. I think this pattern is often referred to as "sand and aqua".
This bubbly yellow is the background in the tortoiseshell pieces, and in other early bits with blue. It is a common feature of Mdina - I don't know why it is so often overlooked that it is bubbly. :?