A second form involves technology used for exploration boreholes in the hard rock mining industry.

小井眼的第二种形式包括使用了在采矿工业中使用的硬岩石中的勘探技术。

youdao

At least 3,350 active mining claims exist for all types of hard-rock exploration within the area.

目前至少有3350个活动的采矿队正在这一地区寻找重金属矿脉。

youdao

At least 3, 350 active mining claims exist for all types of hard-rock exploration within the area.

目前至少有3350个活动的采矿队正在这一地区寻找重金属矿脉。

youdao

Senior Administrator for Cluff Gold,Clifford Patnelli, says mining for gold in the hard rock will be a first for Sierra Leone.

VOA: standard.2010.04.22

The Elimination of Double Subsidies for the Hard rock Mining Industry Act takes on depletion allowances for mineral extraction based industries.

FORBES: Connect

There is free access to 216 million acres or about 9% of all public land for the purposes of hard rock mining.

FORBES: Connect

It will be challenging for the company as it transitions from soft-rock mining to hard-rock mining.

FORBES: High Costs In 2013 Will Continue To Be A Hurdle For IAMGOLD