The US has a long history of producing solid gold coins – old gold coins for sale are relatively common – with some notable exceptions. Canada, South Africa and Australia have also been prolific producers of gold coins over the years.
In another twist to this remarkable story, the first “1804” silver one dollar coin was actually minted in 1834. This came about because the US Department of State wanted to organise a “gift” for Asian leaders when it was organising a trade mission.
The silver spot price is quoted in US dollars – to find the local spot price this dollar rate is simply converted into the local currency – whatever prices silver price is quoted in, it is always for one troy ounce of .999 fine silver.
Back in 1921, the world was a different place. America only ended World War I with Germany, that year, by signing the Treaty of Berlin – until then it was still, officially, at war. The cost of that war was astronomical – and this affected the American economy – not even the 1921 silver dollars escaped these effects.