It's important for expedient to put the different materials. In order to offer optimum usability. The volume of the machine is a bit bulbous in shape, because it better distributes the forces acting from outside. This allows a ceramic mold. In the lower area a two-walled coffee pot is surrounded by ceramic. The stored heat from the roasting process can thus be slowly released to the coffee pot. The concrete base prevents a possible top-heaviness of the machine.
Brave New Coffee World