These include increasing difficulties of mining far below the ground in the key producing nation of South Africa, as well as labor issues that mean higher costs and the threat of supply disruptions due to strikes.

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At that time, a small quantity of US shale oil was being unlocked by mining the rock out of the ground, trucking it to centralized plants, and heating the rock to release the hydrocarbons.

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The threat of a power shortage in the country, and thus a curtailment of electricity needed for mining that tends to occur far under the ground, has been an ongoing issue for a few years now.

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At Surmont, instead of open-pit mining, the bitumen is melted out of the ground by injecting steam.

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Public mineral resources become private the minute you pull them from the ground, meaning the only costs incurred from mining on public land are operating expenses.

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It has put in place a rehabilitation program that aims to reshape the dunes and bring the forest to its pre-mining state by putting the indigenous plants back into the ground after the extraction process.

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All other things equal, the mining of that tonne might raise the value of the coal that remains in the ground, leaving the value of coal assets unchanged.

ECONOMIST: An invaluable environment

Outside the mining sector, strong equity markets allowed some rich-listers to boost their fortunes and gain ground against the commodity crowd.

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The Dwarf King goes from being committed to the productive arts of mining and metallurgy to simply gazing at the veritable sea of gold which he has gathered under the ground.

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