CoorsTek 60112 Porcelain 250mL High Form Crucible, White Glazed High form porcelain crucible is glazed inside and out, except for the outside bottom surface and rim Thermally shock-resistant; To prolong the life of your CoorsTek labware be sure to follow gradual heating and cooling rates Maximum temperature limit for use: 1150-degree celsius Refractory qualities include a fusion point of 1670-degree celsius and a softening point of 1400-degree celsius.