Graphite Crucible 2 kilo, Casting Tool, For Auto Furnace Gold, Silver Brass Bar This is a new graphite crucible designed for the hand held melting furnace. Can be used for all metal types, maximum working temp 3000 c. This model has the groove in the top for the wire type crucible tongs. Measurements : top outside diameter (mm) : 73mm. top inside diameter (mm) : 45mm. height under the top (mm) : 134mm. height with the top (mm) : 156mm.