Key Success Factors for a Good Project, page-24

I had a chat to Steve Tambanis at the Benchmark Minerals conference a few months back, he mentioned that the spheronising process only upgrades the TGC% by about 0.1% at most. My interpretation is that the occurrence of some of the impurities occurs in areas that cannot be separated using mechanical processes only (i.e. without acid or thermal purification, the spherical graphite produced from BKT feedstock is "only" 99.3%TGC, which does not meet battery grade specifications).

Whereas Magnis claim to be able to take a 99%TGC product to 99.8% during spheronising, and then to 99.95%TGC using a thermal coating process. Again, my interpretation is that it's because of the distribution of impurities along the edge/surface of the flake rather than interstitial impurities. The thermal coating process "homogenises" the graphite, ensure an even distribution of impurities across the sample, therefore they do not require an addition purification step in the process.

As for product consistency, they have sampled dozens of diamond drill cores across the entire deposit as opposed to bulk sampling from a single area, so that ore variability across the deposit has been accounted for. Whether this is an appropriate method to ensure for representative product consistency, I can't say, but it's certainly not a case of a one off sample "representing" an entire deposit.