UDPATE 1-Harry Winston posts loss as diamond demand drops

* Revenues plunge on weaker diamond prices and sales

* However, prices rebounded from first quarter (In U.S. dollars unless noted)

TORONTO, Sept 10 (Reuters) - Harry Winston Diamond HW.TO recorded a loss in the second quarter, as plunging demand cut the diamond miner and retailer's revenues nearly in half, the Canadian company said on Thursday.

Harry Winston, which owns high-end jewelry shops and a minority stake in the Diavik diamond mine in Canada's Arctic, lost $24.5 million, or 32 cents per share, in the three months ended July 31. That compared with a year-before profit of $49.9 million, or 81 cents a share.

Quarterly sales fell to $94.8 million from $186.1 million, as weaker prices and volumes of rough diamonds sold cut mining revenues by 56 percent, while the retail segment recorded a 40 percent decrease.

However, the company said rough diamond prices rose from the first quarter and sales climbed near the end of the second quarter, suggesting a shift in momentum.

Harry Winston is part-owned by Kinross Gold (K.TO). The majority owner of Diavik is mining giant Rio Tinto (RIO.L).

The company's shares jumped 9.7 percent to C$8.27 during Thursday's session. The results were released after markets closed.

($1=$1.08 Canadian) (Reporting by Cameron French; editing by Rob Wilson)