YELLOWKNIFE, Northwest Territories (Reuters) – A decline in diamond prices because of lower growth in Chinese jewelry demand is dulling the appeal of Canada’s Arctic diamond industry, with the resulting drop in exploration hurting the region’s long-term prospects. Exploration spending in Canada’s diamond-rich Northwest Territories (NWT), the world’s third-biggest producer, is forecast to drop 54 percent this year, according to a Canadian government estimate earlier this year. That is bad news