illustrated by the following example a mixture was prepared of 3 90 kilograms of wolframite 5 55 kilograms of sodium chloride and 5 55 kilograms of sodium meta silicate this mixture was heated for one hour at 1090 u00b0 c and a tungsten bearing halide phase was formed as described in u s pat no 3 373 097 the tungsten bearing halide phase was decanted from a slag layer containing the remaining impurities and approximately 8 10 kilograms of the tungsten bearing halide was obtained this material was allowed to cool and then pulverized approximately 7 300 grams of the pulverized 40 mesh tungsten bearing halide was mixed with 453 3 grams of natural flake graphite and placed into a crucible made of nickel base alloy 214 the particle size distribution of the natural flake graphite used was as follows 850 micrometers 4 6 710 micrometers 8 5 600 micrometers 17 5 500 micrometers 31 3 425 micrometers 13 0 300 micrometers 12 9 and 300 micrometers 12 2 the mixture was heated to 1070 u00b0 c for three hours and 50 minutes during which time the ingredients became molten and tungsten monocarbide was formed the resulting halide slag was decanted leaving the tungsten monocarbide crystals behind in the crucible the wc crystals were removed from the crucible allowed to cool and then cleaned the cleaning step consisted of a leaching of the wc crystals with a hydrochloric acid solution to remove any residual salt and any metal impurities that the wc crystals may have picked up from the crucible the wc crystals were then gravity separated such as by panning to.