Cost of sales (Tables)

12 Months Ended

Dec. 31, 2017

Sociedad Minera Cerro Verde S.A.A. [Member]

Disclosure of cost of sales [Line Items]

Disclosure Of Detailed Information About Cost Of Sales [Text block]

This item is made up as follows:

	For the year ended		For the year ended		For the year ended
	December 31, 2017		December 31, 2016		December 31, 2015
	US$(000)		US$(000)		US$(000)

Materials and supplies		556,022		496,918		364,234
Depreciation and amortization		456,467		472,997		244,477
Labor (a)		286,058		215,839		146,395
Energy		229,272		229,035		118,019
Third parties services		144,829		100,897		95,087
Change in work in process inventory		51,412		(3,789)		(118,327)
Management Fees		2,867		2,793		3,565
Change in finished goods inventory		2,060		(3,951)		467
Other costs		39,251		42,301		8,087
		1,768,238		1,553,040		862,004

(a)

Labor includes an expense of US$86.4 million related to profit sharing for the year ended December 31, 2017 (US$36.8 million for the year ended December 31, 2016 and credit of US$1.6 million for the year ended December 31, 2015).