Tulowice egg cups, Poland, caramel and mustard glaze

A set of six charming glazed ceramic egg cups in a beautiful color between caramel and mustard, very soft and cozy, with a simple and elegant, rounded shape. They are stamped "PT Tulowice, made in Poland." The city of Tulowice has been known for its ceramics since 1852, but it's difficult to find out more about this particular manufacturer (I don't read Polish, but I would be delighted to learn more if you have any information). They are thought to date from the 1970s when this color was very fashionable. They are very practical with their "integrated" cup that prevents the egg from leaking everywhere, and their shape without unnecessary details makes them easy to clean and allows them to be stacked for storage without taking up too much space. They are in perfect condition, with no cracks or chips, just a small spot, an original flaw, in the glaze on the rim of one cup (visible in the last photo). They measure 11 cm in diameter and 3 cm at their highest point.