The stove is cast in a conical metal mould consisting of two parts. The smaller part is placed inside the larger one. There is a space of 33 mm between the parts. A mix of burnt local bricks that are crushed and mixed with cement, is poured into the mould. A curved piece of wood at the bottom of the mould provides for the opening that allows air to get to the charcoal placed on a conical loose slab inside the stove. The slab is cast inside the smaller mould where a round metal plate rests on three small nodules. The cement mix is poured on to the plate, two inches thick, and left to harden until the following day. After 15 minutes, five to seven holes are punched in the slab with small pieces of conduit pipe. The casting is left to harden until the following day. The outer part of the mould springs open when its lock is released. After removing the inner part of mould, the cast slab inside it is removed. For more information see www.improved-stovesandchimney.com