Rough diamond sales at De Beers slumped by 96% to $56m (£44.6m) in the second quarter of the year, down from $1.3bn recorded the year prior.
This was largely driven by lower volumes, which plunged by 97% to 300,000 carats in the prios, while prices also fell.
It comes after the company cancelled its third sales event of 2020 in light of Covid-19-related travel restrictions, while offering sightholders the option to defer up to 100% of their allocations at the fourth and fifth sales this year.
According to its latest production report, the average realised rough diamond price decreased by 21% to $119(£95) per carat in the first half of 2020, down from $151 (£120) per carat recorded the same period the year prior.
This was driven by a higher proportion of lower value rough diamonds sold, as well as an 8% reduction in the average rough price index.
Rough diamond production also decreased by 54% to 3.5 million carats in the second quarter, primarily due to the Covid-19 lockdowns in southern Africa.
After mining operations resumed, production still remained at lower levels, reflecting the reduced demand for rough diamonds in light of the pandemic.
In Botswana, production decreased by 68% to 1.8 million carats, while South African production decreased by 3% to 0.6 million carats primarily due to Covid-19 measures. In addition, production in Canada decreased by 27% to 0.8 million carats in the same period.
According to De Beers, the demand for rough diamonds was “significantly impacted by a combination of Covid-19 restrictions impacting consumer demand and access to southern Africa, as well as severely limited midstream cutting and polishing capacity due to lockdowns, particularly in India.”