Edward Jay Epstein wrote on this in 1982, the de Beers cartel has been propping up natural diamond prices for decades. It's deep in Veblen goods territory.
The Argyle mine stopped digging up pink diamonds, I am pretty sure it's to maintain value of the stocks in circulation and held by the company.
I'm pretty sure Rio tapped out on Argyle as they had worked their way through the entirety of the alluvial deposit after 35+ years of extraction.
They were very keen to find a lode source kimberlite pipe and get more pink diamonds but sadly .. no show (as of the last time I looked at the Tech. Reports on regional exploration).
There was absolutely a financial element on the decision to shutter and rehab the mine site .. but it was driven more by diminishing returns at that deposit than by market starving.
They don't seem to have any plans to reopen as they're supposedly going into full rehab mode (all equipment gone, return to nature):
They had a very nice stockpile of investment grade pinks afaik and cashed them in for a while with an annual release. The Web agrees with you, the mine stopped being economically viable. I think I just read 95% of it was bort and so industrial anyway.
Readit News
The Argyle mine stopped digging up pink diamonds, I am pretty sure it's to maintain value of the stocks in circulation and held by the company.
They were very keen to find a lode source kimberlite pipe and get more pink diamonds but sadly .. no show (as of the last time I looked at the Tech. Reports on regional exploration).
There was absolutely a financial element on the decision to shutter and rehab the mine site .. but it was driven more by diminishing returns at that deposit than by market starving.
They don't seem to have any plans to reopen as they're supposedly going into full rehab mode (all equipment gone, return to nature):
https://www.riotinto.com/en/operations/australia/argyle
https://minedocs.com/26/Discovery-and-Mining-of-the-Argyle-D... is old but fascinating and had great photos and maps.