In harsh environments stainless steel sheath or Inconel sheath can be used to protect the thermocouple and protect instrumentation signals from electrical interference and reduces Thermocouple Splatter Problems for kiln firings on your Pottery.
Maximum temperature of 1170 Deg C constant or 1300 Deg C intermittently for kiln firings.
Inconel Sheathed Thermocouples Type K 6MM Sheathed (NON Grounded) with Socket and Flange
Suit Skutt, Evenheat ,Paragon and many others
Thermocouple information and instructions