Does Anyone Remember The Silver Bar Craze Of The Mid-1970-S?

Yeah, I do.
For a few months, I became a walking encyclopedia on the ASW of most World and Australian junk silver coins that were commonly available.

I cherry picked my way through a few thousand World silver coins, and was able to make average purchases at around 70% to 80% of the silver value for most coins.

Luckily enough along the way, I also found a few decent silver coins with a decent numismatic premium, for which I was able to obtain for little over their silver value.

I sold the junk silver, and bought some nice numismatic World silver coins with the proceeds, and those coins remain in my collection.

I did buy a half Kilogram poured silver bar as the silver price was rising, and sold a little too late after the silver price peaked. I broke even, and was lucky enough to just get away with that one.
Two things learned:
1. Never speculate on the bullion value, and
2. Stick to numismatic coins, and forget about their bullion value. Just cherry pick to buy well, and only buy below market value for a particular coin, across the whole of numismatics. By casting your net wide, bargains are easier, and more numerous to find.

Three cheers to the Hunt Brothers for setting the whole scene up in the first place for me.
I am not expecting this to happen again in my lifetime, at least.

No, but my local LCS owner thinks I'm a fool for collecting any old low mintage art bars, he puts them in the junk bin.