八十年代初,许多铜矿工程开发的可行性研究是以1美元/磅或更高的铜价为基础的。甚至当铜价自1980年平均为0.97美元/磅降至1982年平均为0.65美元/磅时,一些公司仍在讨论在铜价的“暂时性”下跌过后开发他们那些费用较高的铜矿。直至1983年末,大多数人认识到了在一较长的时间内铜价很可能回升不了,开发费用高的铜矿的议 In the early 1980s, the feasibility study for many copper mine development projects was based on copper prices of $ 1 per pound or more. Even when copper prices dropped from an average of $ 0.97 / lb in 1980 to an average of $ 0.65 in 1982, some companies are still discussing the development of their more expensive copper mines after the “temporary” fall in copper prices. Until the end of 1983, most people realized that in a long period of time the price of copper is unlikely to rise again, and the high cost of developing copper mines