So far, from my understanding, the sample size of the material has been small enough it's been difficult to rule out resistance from corrosion on the contacts of the sensors, though I seem to recall a post not too long ago on here about resistance below the threshold of measurement around 100 degrees k.

The compound must be tricky to synthesize with a good degree of purity- I think we'll learn quite a bit more if someone manages to get a bigger sample than a flake the size of the point of a needle.