...Return to Low-Cost Production: Compania de Minas Buenaventura S.A.A.'s cash cost of production returned to historical levels in first-quarter 2016 following a period of higher costs amid weak commodity prices during 2015. Buenaventura's ability to maintain its low cost of production is a key consideration in revising the Outlook to Stable. Leverage to Remain Low: Fitch Ratings projects the company's net debt/adjusted EBITDA will remain around 1.2x during 2017, driven by higher metals prices, increased volumes sold of zinc and copper, and a reduction in operating costs. Net leverage is expected to be more in line with the company's historical average. Buenaventura's credit metrics deteriorated rapidly in 2015 as weak commodity prices, the closure of its Breapampa mining operations and higher all-in sustaining costs at several of its consolidated mines negatively affected profitability. Low-Cost Stand-Alone Operations: Buenaventura operates four fully owned mining operations with production...