An annealing tray made of a piece of sheet iron in the shape of a box about 18" square and 3" deep, with the corners lapped and riveted and filled with slag, answers very well, but one similar to the illustration, Figure 1, is better. In this the top is circular and rotary, which is an advantage. A pair of light long nose-tongs are needed to handle the work. Any ordinary foot bellows and blow-pipe will do.
Figure 2.
Plate 1.