Once you get past the amount of gold coins a Scotsman can carry in his "sporran",gold becomes pretty unwieldy as a means of payment.
Apart from Jewellery,fairly minor use in Electronics ,& a few other "niches",it is not really necessary to modern society.
The productive capacity of a country,in terms of useful products to feed its people,house them,etc,is really a much better basis of currency value .
Fortunately for gold producing countries like Australia,people haven't caught on to this fact.
Indeed,the world desire for gold was the engine that drove much of the early development in this country.