SHANGHAI, Dec 5 (SMM) - Pure nickel inventory in six regions totalled 7,046 mt last week, down 145 mt from last Friday. Nickel briquette inventory fell 100 mt WoW to 620 mt, and the nickel plate inventory fell 45 mt WoW to 6,426 mt. Due to the closed import window and high nickel prices, the overall decline in pure nickel inventory last week was limit. In addition, although the nickel sulphate produced with nickel briquette was less cost-effective, some nickel salt plants purchased nickel briquette in the form of long-term orders. Some Stainless steel mills also purchased nickel briquette.