Potty about pottery

It's so exciting spotting a piece of white pottery on a windswept beach only to turn it over and discover a beautiful pattern. This unusual green and white gem was found by my sister (one of my sea glass gathering fairies!) on Gardenstown beach on the stunning Moray coast. I wonder what it was, a fancy plate or jug maybe? I've paired it with recycled Sterling silver and copper. Upcycling at its best!