De Beers sold $540 million of rough diamonds in its December cycle, buoyed by the return of Indian manufacturers from their seasonal holiday shutdown, the company said Tuesday.

Revenue from the 10th cycle, including last week’s sight in Botswana, jumped 22% from $442 million during the previous cycle. Proceeds climbed 19% versus a year ago.

Sales “continued to be in line with expectations ahead of the all-important retail selling season, as cutting and polishing factories in India restarted their operations following the Diwali holiday,” said De Beers CEO Bruce Cleaver.

Indian factories typically close for three weeks over Diwali, which this year occurred on November 7. The market usually picks up after the festival as manufacturers reopen and buy rough so they can ramp up operations. They also use December to prepare for an anticipated increase in polished demand in the first quarter, when dealers and retailers look to replenish stocks they deplete during the US holiday season.

De Beers’ rough-diamond sales rose 2% to $5.39 billion this year, according to Rapaport estimates. That includes 10 sights across the year, as well as auction proceeds.