Right now during this Covid-19 pandemic, if you want to stack, I would go to "junk" silver as I have found multiple lots on eBay for UNDER spot. Granted, I search by newest auctions and define my results by "best offer" as I can grab silver on the cheap by throwing a respectful but cheap offer. Works probably 50% of the time which is fine with me, if they decline....on to the next.
It's really doing the same thing it always really does. When spot goes up prices rise, when spot falls prices hold for a while. Just always remember that when someone is trying to hype how metals will go up or how worthless the dollar will be as a seller they're more than happy to trade metals for dollars