In 1955, the Experimental department was founded where young, recently graduated ceramists can fully experiment with the materials of the factory. This non-commercial initiative focused on the renewal of ceramics as a form of coast, which was unique for the Dutch business community, which, after all, derives its existence from commercial activities and making a profit. Theo Dobbelmann, sculptor, ceramist, and teacher of ceramic technology at the Institute for Applied Arts Education in Amsterdam, therefore initially refused to take charge of this department, convinced as he is that commerce and art do not go together. Fortunately, the management manages to convince him.
The first artists to come and work here are the ceramists Lies Cosijn, Jet Sielcken, Sybren Valkema, and Emmy van Deventer. In March 1957, the Rotterdam Museum Boijmans van Beuningen organized the first exhibition of this foursome. This exhibition is an overwhelming success, with the result that the experimental work is exhibited elsewhere in the Netherlands and abroad. This is followed by many novice ceramists.
The Experimental department was closed in 1977 for economic reasons and a large art auction was organized with works by more than 20 international ceramists associated with the department.
Work from this Experimental department can now be seen for the first time in the renewed Royal Delft Museum. Also, work by Lies Cosijn who worked from 1955 to 1962 as one of the first employees in this department. In 1988 she was asked to design the first object for the Modern Ceramics Collection. This vase is therefore on display as part of the Modern Ceramics Collection.