Hey this may be common knowledge but I was pleasantly surprised today to see kaowool at rona. It was by the heating duct stuff. https://www.rona.ca/en/insulating-ceramic-wool-p1243093 I only do stock removal knives so far so my 2 brick forge has sufficed for heat treating. I have been holding on to an old propaine tank and I stole the pressure regulator off an old bbq. Basically have been slowly acquiring the parts for a real forge. Seeing the the wool at rona today got my mind going and then further down on the same shelf I saw this. http://www.imperialgroup.ca/stove_maintenanceproducts.cfm?c=322 In the msds it lists Alumina Silicate and Portland cement. I recognized Alumina Silicate in regards to using borax but can't remember if that's what you want or if that's the stuff that borax eats. Seems too easy but maybe somebody with more experience can chime in?