RAPAPORT... Rough prices jumped at Petra Diamonds' sixth tender of the year as demand increased.The June sale realized $93 million, up 8% from $86.1 million in May, the miner reported last week. Like-for-like prices rose 8%. The average price climbed 21% month on month to $163 per carat, according to Rapaport calculations. The growth came even as Petra did not sell any special stones during the June tender; in May, a 13.74-carat blue diamond fetched $5.7 million."The significant interest shown at [this tender] bears testament to the ongoing strength of the rough-diamond market," said Petra CEO Richard Duffy. While prices have been positive across all categories, the miner has seen "particular strength in the prices of both white and colored gem-quality stones over the last 12 months."The company sold 569,496 carats at the tender, compared with 635,806 carats in April. The sale was Petra's final one of the fiscal year, which ended June 30.For the full year, Petra sold 3.5 million carats of rough across six tenders, totaling $584.5 million. That compares with 4 million carats over six tenders last year, which brought in $406.9 million. Like-for-like prices for fiscal 2022 surged 42% versus the year before.Petra will release its results for the fiscal year on July 19, it noted. Its first tender of fiscal 2023 will take place between August and September.Image: Rough diamonds from Petra's Koffiefontein mine. (Petra Diamonds)