This hole into the underground ramp up to more than 1000 meters, the scenery is magnificent, unfathomable, is called the North the first hole.

此洞斜入地下长达一千多米，景色瑰丽，深不可测，被称为北国第一洞。

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Freeport blamed this drop largely on changes to mine plans at the Grasberg mine in Indonesia, which delayed access to higher-grade material, and a slower-than-expected ramp-up at the Deep Ore Zone underground mind.

FORBES: Freeport Copper, Gold Output Falls In 3Q But Expected To Rise Again As Indonesian Production Picks Up