Price levels in the 19th century fluctuated thanks to Al Hamilton's heirs screwing around with the nation's monetary policy. As for gold, I once again invite you to look up the current value of .95 ounces of that material today. For comparison, in the 1850's it was minted into and used as a face value coin of $20.
In the modern age, when most money consists of entries in computer databases, there is no way lumps of metal could be the basis for economic transactions.
Sure there is. Physical commodities of value are traded electronically all the time, often with their owners never even seeing or holding them. Have you ever heard of taking out futures? When you buy oil futures do they physically deliver a load of crude oil barrels on your front lawn for you to sell at a different time? Or do they process the thing electronically and sell it on the market where, pending the success of your investment, you gain from it.
In economics, you get an F.
Not at all, though I could easily assign you that grade in principles of capitalism. I suppose what you peddle could be called "economics," but it certainly isn't the capitalist kind.