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美国《工程与采矿杂志》一年一度的矿山与选厂工程调查表明,1988年的建设项目为481项(表见第15页),略高子1987年的477项,但总的预算投资额却从1083亿美元降至801亿美元。这主要是有几个已建设多年的大型项目从统计表中消失,而另有几个大型项目因经济上无利而被撤销之故。黄金及其他贵金属方面的投资继续增加,但近期贱金属
A survey conducted by the United States Journal of Engineering and Mining’s annual mining and dressing plant project showed 481 construction projects in 1988 (see page 15) and 477 slightly higher children in 1987, but the total budget investment But fell from 108.3 billion US dollars to 80.1 billion US dollars. This is mainly due to the fact that several large-scale projects that have been built for many years have disappeared from the statistical tables and that several other large-scale projects have been canceled because they are economically unprofitable. Investments in gold and other precious metals continue to increase, but recent base metals