John Cuthber, It needs to be calibrated for K2O. Because in my department it is going to be used to measure bottom ash which contains a lot of different things. It is recommended to oxidize the samples before making the fused beads out of them. I have KHCO3 available here, so i need to do a loss on ignition first to burn out the H and CO2 Which brings me to the next problem because I've read that CO2 can be removed at 1200oC, which is also quite high and relates to the first problem because our normal crucibles can't handle this.
StringJunkyBut does this say something about the 1065oC, I mean, will the platinum react with the potassium then?
PyrineA graphite crucible might work, although my supervisor wasn't so happy about it, don't know why. I don't think the environment is inert.