Citation please. I've seen no actual concrete evidence that Elon inherited any significant sum of money from an "emerald mine." This seems to be one of those internet myths which lives on in forums despite no credible evidence.
"After Maye and Errol divorced in 1980, Elon mostly lived with his father, who says he owned thoroughbred horses, a yacht, several houses and a Cessna"[0]
"Errol returned to South Africa with a half-share in a Zambian emerald mine, which would help to fund his family's lavish lifestyle of yachts, skiing holidays, and expensive computers." [2]
[0] https://www.mercurynews.com/2014/04/10/2014-rocket-man-the-o...
[1] https://www.nytimes.com/2022/05/05/world/africa/elon-musk-so...
[2] https://web.archive.org/web/20211122143742/https://www.busin...
And at one point his father made a small investment in a mine. And even that is grounded on shaky evidence.
This mine investment might have been profitable (we dont know) but the idea that his family had some waste emrald mines is nonsense and that investment certainly didnt make the family rich.
And given their bad relationship, Elon lost support from his father when he came to US/Canada.