I saw this Polish Pottery on display at a store in the old town of Krakow while visiting the old town square this weekend.
They are marked with the manufacturer logo, pattern, and 'Made in Poland' sign. The use of the Color Blue is evident in the white ceramicware, with floral or dotted patterns spread across, carrying a mix of other colors.
Since the design differs from the widely available English or Asian-style ceramicware, Polish Pottery carries some premium. The traditional pieces are stamped with 'UNIKAT.' At the bottom, it indicates it is a rare or better quality product that commands a higher price.
It makes for an excellent souvenir item to gift, but fragile enough to carry during travel.
Here's an article explaining pottery mark types in detail.