De Beers lifted diamond prices at its third consecutive sale as an industrywide recovery from the coronavirus pandemic gathers pace.

The world’s biggest diamond producer raised prices by about 4% at its second sale of the year, according to people familiar with the situation who asked not to be identified because the information is private.

A spokesman for De Beers declined to comment.

Diamond prices are rebounding after the pandemic brought the industry to an almost complete standstill in the first half of last year. Strong holiday sales in the U.S. and positive signs from the Lunar New Year have seen buyers rush to replenish their stocks of rough stones.

De Beers is tapping that demand after the Anglo American Plc business was forced to make deep price discounts last year. The increase at this week’s sale in Botswana follows price gains of about 5% last month, the biggest in years. The company also edged prices higher in December.

The price rises were once again focused on the biggest and most expensive diamonds. Prices for rough stones that would produce a 2-carat to 4-carat polished gem climbed more than 7%, the people said.

The price increases at the two previous auctions didn’t deter customers — the cutters, polishers and traders who dominate the industry’s midstream — with De Beers reporting its biggest sale in three years in January. Still, some industry participants have raised concerns that the market is running too hot, risking a slump later in the year.

The strong sales so far will be a boost for Anglo American, which is set to report earnings later this week. Its peers have already given billions of dollars in dividends back to shareholders, amid surging prices of commodities including copper and iron ore.