As prices for the company's four key "pillar" commodities —iron ore, metallurgical coal, copper and oil and gas — have all dropped to multi-year lows in the past 12 months.
The price for the two assets could rise to $500m from $200m, depending on an eventual recovery of copper prices and the execution of an expansion plan for the Mantoverde mine.
The US has suspended the futures market on the Nasdaq index, as panicking traders have driven it down 5% — the maximum allowed under Wall Street rules.
Appian Capital founder Michael Scherb: "You're now seeing the same changes in mining that happened in oil and gas which is now heavily supported by PE"