The apparatus consists of a heating element within a conical shape refractory crucible, which is enclosed, in a stainless steel case with proper insulation. The case is mounted on top of a stainless steel cylinder, which forms the support. Perforations provided at the lower part of the support and a concentric gap is left between the refractory case and the support, which prevents any temperature rise. The element attains the temperature range of 800⁰C to 1000⁰C and consumes 350 W with an energy regulator box to control the temperature. Working temperature 600⁰C to 700⁰C.