By Will Wade

(Bloomberg) U.S. miner Contura Energy Inc.’s $800 million bet on international coal markets is souring.In November 2018, when Contura bought Alpha Natural Resources and became America’s biggest supplier of metallurgical coal, global prices for the fuel were climbing — bolstered by demand, particularly in China. Since then, trade tensions have escalated, curbing purchases of both steel and the coal used to make it. On Thursday, the miner reported $40 million in third-quarter earnings, less than half of what analysts estimated, and suspended share buybacks.The stock plunged by the most ever and was trading at a record low Friday. It’s fallen 87% this year.Contura has “endured an incredibly tumultuous and unnerving 2019, marked by management changes, asset sale challenges, and most importantly, a significant deterioration in met coal market fundamentals,” Mark Levin, a coal analyst at Seaport Global, said in a research note. “As a result, the stock has come unglued.”

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The collapse of Contura, which declined to comment, reflects the broader struggles in America’s coal country. U.S. power plants are burning less of the fuel as utilities shift to cheaper natural gas and renewable energy. And the met coal export market that miners were depending on to weather this downturn at home is weakening. At least four U.S. companies have shuttered mines since August and five have gone bankrupt this year.

Met coal slumped after Contura bought rival Alpha

This is not the market that Bristol, Tennessee-based Contura had envisioned. Coal prices, now near a two-year low, came in “significantly below expectations” in the third quarter, Chief Executive Officer David Stetson said in a call with investors Thursday. “Contura, as well as the industry as a whole, experienced weakening demand for our products.”

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On top of lower coal prices, Contura reported higher production costs at mines where it makes the type of coal burned at power plants. The company blamed lower worker productivity due to vacations and the time needed to move around equipment for that.

The company’s shares plunged 49% on Thursday. They were down another 7.1% to $8.71 at 1:54 p.m. in New York.

Contura said it expects production costs to come down next year and noted that much of its output for 2020 is already sold. But prices may not prove high enough to generate significant cash flow for the miner, said Andrew Cosgrove, a mining analyst with Bloomberg Intelligence. “They’re still looking at burning cash,” he said.