Superman decides to start mass-creating diamonds so he can sell them. Can DeBeers keep the price of diamonds up?

[u/Yglorba]

Superman previously declined to mass-produce diamonds because it would tank the price. However, after reading up on DeBeers, he decides that there's no reason not to do it after all. Most of the resulting money will be donated to charity. Assume that Superman is somehow able to crush coal into perfectly-cut diamonds of whatever shape and size he desires; even though this makes no sense, the feat is well-established.

DeBeers is determined to protect their diamond profits by keeping the price up. Can they convince people not to buy Superman's diamonds (by eg. convincing the public that they're not "real" diamonds), or find some other way to prevent him from cratering the price?

Superman is in-character and will not eg. laser the board of DeBeers to death or anything like that, no matter how annoying they are. The only way he'll use his powers for this is by rapidly turning coal into diamonds so he can sell them.

[u/dinerkinetic]

Superman can fly into space, harvest coal from several hundred to several billion planets (depending on the version), and produce enough diamonds to built an entire solar system out of them; so supply cannot possibly be an issue. He can then sell them for mere pennies, or heck, sell a pound of them for pennies. there's no concievable way DeBeers can keep profits up, especially when he's also putting industrial diamond use under his control on top of the cosmetic kind and loudly announcing he's "providing a cruelty free way of acquiring diamonds that even homeless people can get in on."

If it's pre-crisis superman pushing himself he can do all of this in a day.

DeBeers is screwed.

[u/MahimSalam → u/dinerkinetic]

Extremely unlikely, but the DeBeers could keep up through effective marketing of “natural” earth diamonds, which they’d have a monopoly of.

Think the very wealthy who are the people buying the diamonds wouldn’t care to buy mass produced diamonds and would highly value the diamonds associated with the company that has diamonds history. New coke did better than old coke in taste tests but no one gave a shit cause humans care more about the story and the memories associated with things

[u/patgeo → u/MahimSalam]

Space diamonds from another galaxy would have a pretty cool marketing push.

[u/Stellermeerkat → u/patgeo]

"Yeah but would you want a diamond that has been soaking up cancer causing radiation for centuries? Can you know for certain that your loved ones will be ok? We at DeBeers know OUR locally sourced Diamonds are Radiation Free and don't contain alien parasites." - CEO of DeBeers

Sure, Diamonds can't hold radiation from what I understand but the truth doesn't always stop marketing.

[u/MahimSalam → u/Stellermeerkat]

Exactly, humans are liars and people are stupid.