must free of anything ending -ate (except stearate) or -ic acid; free of magnesium except magnesium stearate (it’s insoluble)
The only product you link violates this. It contains stearic acid...
edit: Chris explains this here: https://chrismasterjohnphd.com/podcast/2016/12/26/zinc-definitely-fights-colds-youre-probably-using-wrong-kind/#comment-48164
″ The stearate isn’t a problem. I was trying to simplify. ”
Completely agreed. I even publicly announced on my Facebook when Bitcoin was 7 USD that I was buying 100USD worth, but then once I looked into how to even convert USD to Bitcoin, I said “eh, not worth, even it for some interesting economic experiment”.