Pieter Claesz found a lifetime's work in the changing aspects of ordinary things. His vision altered with the passing years, but even when he was quite old, he continued to express himself through skilled arrangements of shifting light and shadow and casual groupings of lifeless objects. His entire oeuvre comprises still-life paintings, and in his numerous, small-sized paintings, two periods can be distinguished: the earlier, lasting until around 1620, is in the style of the older painters of the School of Haarlem and consists mainly of banketje or banquet pieces. In the later period he turned to "breakfast pieces," a simple meal painted at eye level in monochromatic harmonies. He is considered the founder of this particular style, together with his contemporary, Willem Claesz Heda, also a still-life painter. This characteristic still life belongs to the mature and best period of the painter. The heavy Bohemian-glass roemer (goblet) is one of the artist's most cherished subjects. It appears in many of his paintings, always half-filled.