I think I found the answers I was searching for as to why the specific metals that were historically used as currency (think current, as in electrical current) were.
The most conductive metals evidently propagated EM fields which made people's behavior fall into sync and the ruling class picked up on it and figured out how to manipulate people using the EM fields that the metals were propagating.
At a time when there were relatively few people in direct contact with smelted, elemental metals, it wouldn't have taken a genius to notice any marked changes in the behavior of those who were.
If the rulers saw more orderly behavior occuring among people around the metals, they would have figured out that the metals were exerting some kind of influence that made people's behavior more uniform and controllable, thus predictable.
Silver is the most conductive of all metals. The Hebrew word for money is kesef: which means both silver and to be drawn to.
They felt the drawing power (magnetic radiation) of silver, gold, copper. Perhaps they saw that in the presence of idols made of gold and silver people acted differently. Perhaps, in addition to "lining up" in orderly fashion in the EM field, they lost contact with the magnetic field of the Earth and so lost their orientation – thus becoming far more vulnerable and lost.
When people used metals as methods of exchange, they absorbed some of the molecules of the metals into their bodies, thus becoming more "conducive". The practice of wearing silver and gold and copper jewelry would increase this effect.
I believe that from the time of the Babylonians it was noticed that having elemental metals of the Group 11 Elements (1B) would cause them to fall into sync and they were more easily controlled. Those metals are optimally malleable as well – every ruler's dream quality in the populace it rules.
The Jewish Temple was constituted such that the effects of the metals was somehow neutralized within the confines of the Temple.Entering the Temple, the current was broken. Having experienced being freed of the EM field that induced herd-like behavior, people had the memory of independent action and though. They knew what it was to have the spell broken. Thus, the Temples had to be destroyed - first by the Babylonians, then by the Romans.
Just at the time that scientists were learning about electrons and protons, they began to talk about going off the gold and silver standards.
I believe they realized they could get the same EM fields propagating more cheaply and perhaps more effectively. I believe that was what the alchemists were trying to do, but it wasn't until the advent of true Chemistry and Physics that the possibility became realized.
There was no more need for the precious metals to be the basis of currency (current, as in electrical current). Now, there's Smart Dust to do that.
How do we unplug ourselves from the grid?
Doreen Ellen Bell-Dotan, Tzfat, Israel