Well David, ZEN states:  "using an environmentally friendly process that consists of grinding, floating and caustic treatment using sodium hydroxide instead of aggressive acids. This purification method has produced a carbon purity of >99.9 per cent in bench-scale tests." and ""The Zenyatta graphite deposit can be upgraded without the use of aggressive acids" (The large scale was not me, it was a factor of the original post.)

They say "instead of" acid and "without the use of aggressive acids", which is only true for part of the process. And they reached >99.9% using all NaOH in multiple rinses, not the process with HFl. Further, that news release says reaching 99,9% may be "impractical", so saying they exceed 99.9% is certainly a questionable claim.

Just keep denying and posting like I'm an idiot. It doesn't matter. Neither of you will address a simple question dealing with how you feel about an obvious discrepency