Owing to ore properties and other causes the quality of iron concentrate was not up to the standard and the enterprise Suffered heavy economic losses after concentrator put into operation.

七宝山硫铁矿选矿厂投产后，由于矿石性质等原因，铁精矿难以达标，经济严重受损。

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For Newmont, the lower ore grades have been a cause of concern as the company faced production losses at the Boddington mine last year.

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