Making the clay finer by chopping with a metal ruler. The two rings in the corner will screw together to form a small mold for casting later. I never thought delft clay is used for other purposes than making earthenware.
Delft™ Clay Casting System - RioGrande
Delft Clay Casting Tutorial
Trying to cast this clay model in tin using delft clay method
Original Delft Clay & Casting Frame Cast Iron Mold Sand Flask Set
Jewelers Equipment Tools and Supplies
Delft Clay Casting Sand 4.4 Pound Made in Netherlands
Technique: Delft Clay Casting – DESIGNYARD
Delft Clay Casting Kit
Delft Clay Original Casting Sand Kit Gold Silver Pewter Aluminum -Set Includes Ring
Delft Modeling Clay Kit
Delft Casting Technique
Delft Clay Sand Casting Set With DVD and Aluminum Mold Frames Gold