Bimetallism? How is that supposed to work? I ask that because its two metals are likely to have varying relative prices.
Not as long as both are difficult to find, and fairly useless for anything other than as money. That mostly held true in the pre-industrial world, with some notable exceptions such as the Spanish bringing large amounts of gold to Europe from their raids in the Americas.
As soon as that stopped being the case for one (silver was both found in large quantities in the Americas, and used widely in new industries such as photography, preservatives for timber, and braising alloys, including solder) the whole thing fell apart.
Gold was found in historically large quantities in the gold rushes contemporary to these changes to the supply and demand for silver; But the relative sizes of these discoveries were very different, and gold remained (as it still remains) pretty much useless.
Finding a sufficiently useless token to represent money, while simultaneously maintaining constraint on (or better still, control of) the supply of those tokens, has been a headache since money began. The big problem is to stop people from copying your chosen tokens, and thereby getting rich while destroying your economy with inflation.
Gold served well in the fairly stable economics of pre-industrial societies, but wasn't adequate thereafter due to deflationary consequences of the money supply's lack of scalability (the rate at which new gold is mined has no relationship to the rate of growth in a fast growing economy).
Ultimately, money is a synonym for value, just as energy is a synonym for work. In both cases, there are a bunch of units you could use; Dollars, Yen, ounces of gold, peppercorns, etc. for money; Calories, Joules, ergs, etc. for energy.
The difference lies in the fact that value is an opinion. So each item has a value that varies from person to person, from place to place, and from time to time.
We can, however, still measure value; We simply ask for people's opinions.
Gold, for example, according to the Perth Mint website, is currently worth between AUD3,115.30 and AUD3,086.77 - that is, the opinions of the people who are looking to obtain some gold right now, and have published that opinion to prospective sellers, is that the maximum value of a troy oz of gold is AUD3,086.77; The opinion of the people who have gold that they are prepared to sell, is that the minimum value of a troy oz of gold is AUD3,115.30.
These opinions vary constantly; As soon as the opinions of buyers and sellers overlap, the mint makes a trade that both parties are happy with - and trades continue until once again the "bid" price falls below the "ask" price.
Some people are very unhappy with the idea that value or money are mere opinions. They prefer to imagine that the (often physical) tokens that represent these opinions have some "intrinsic worth". Of course, that's the last thing we actually want from our monetary tokens; It muddies the waters if people are using their banknotes as a source of notepaper, lavatory paper, or wallpaper.
Gold, like paper, was a good monetary token, precisely because it had little use as anything other than money, so its value could be purely an expression of the opinions of the value
of other goods or services, relative to that of the conceptual money, without the value of the physical tokens themselves confusing the issue; And perhaps more importantly, the money supply wouldn't fluctuate due to tokens being used up for other purposes.
Gold was used as money for centuries, in part because it is intrinsically pretty much worthless, which is a very useful quality for any physical token that we want to use to represent the pure opinion that is 'value'.