Yep. I originally included that and erased it for some reason.

You are probably right about 2 as well, the reasons I like to think they might have been aware: 1.) there were Amphora made of both silver and gold; and 2.) they recognized the antimicrobial properties of other things (example: honey on wounds to avoid infection).

Obviously the Amphora could simply be chalked up to displays of wealth, but I would think they observed the delay in food/beverage degradation in those Amphora compared to standard clay. I guess the funny thing with gold is even today we don't have broad industrial usage (probably good because of the limited supply), though I I suppose trace amounts are used in some modern electronics.