David, you are wrong. As I said, my criticism was NOT directed at the competitors. It as certainly not directed at you. I didn’t mention any names – no reason for you to be defensive.
I did not answer the original question because it was about the discrepancy and confusion, and had to be answered by the author of the review.
I suppose you consider it payback of some kind to accuse me of not knowing the answer. I actually gave the answer, which is “Look at the diagram”.
It’s true that I have little interest in competition, but I’ve been in the part-time lapidary and mineral business for about 55 years, and a reasonably accomplished faceter for 15+.