Abstract: A heat concentrating device particular useful for firing objects formed of metal clay includes a preferably frusto-conical body with a hollow interior surrounded by a continuous sidewall, a wide lower end or base, a relatively narrow upper end, a support screen disposed across the upper end for supporting objects to be fired, and an aperture adjacent the upper end for insertion of a temperature sensor connected to a pyrometer assembly for monitoring the temperature at the upper end of the body. The device is placed over a stove burner to capture the heat emitted by the burner in the interior of the body and concentrate the heat at the upper end of the body so as to heat objects placed on the support screen to a suitable firing temperature.