I’m not sure that’s necessarily true (or at all relevant) for a lot of precious or rate materials like gold. I don’t really know but I’d bet that gold requires much, much less labor to process than steel.
It’s just much more scarce so the people who own the mines can charge more for it.
Even high grade gold deposits are only around 10g/tonne or 1 part per 100,000 so you have to process a huge amount of material to recover a tiny amount of gold. Total world gold production was just 3000 tonnes in 2023.
By contrast a tonne of steel requires about 2 tonnes of iron ore and 0.8 tonnes of coal and 0.1 tonnes of limestone, all bulk minerals dug out of the ground. Total world steel production was 1.9 billion tonnes in 2023.
Yes, I would assume that certainly correct by weight/per kg. I was thinking more about per $ i.e. a gram of gold costs $100 I’m too lazy to look for exact figures but I would bet that labor costs (maybe even combined with energy costs) make up a very small proportion of that.
Profit margins seem to be about 50-70% currently but historically it was closer to 30% (of course that’s still many times higher than for steel production)
The profitability will depend on the production costs for each mine. Those at the margin set the price. If it stays high long enough new mines will open or too low and unprofitable mines will close. The excess profits earned by those that have easily accessible high quality ore are known as 'resource rents' but eventually they will be fully exploited and have to close.
Apparently a great uncle of mine found gold on his family farm in Scotland, but it was never profitable to exploit so saw no benefit from it!
There is also economies of scale. Steel is much more useful than gold. This means investments on improving mining and processing will lower the costs in the long run.
It’s just much more scarce so the people who own the mines can charge more for it.