Inventories, Including Long-Term Mill and Leach Stockpiles (Unaudited)

9 Months Ended

Sep. 30, 2015

Inventories, Including Long Term Mill and Leach Stockpiles [Abstract]

Inventories, Including Long-Term Mill and Leach Stockpiles

INVENTORIES, INCLUDING LONG-TERM MILL AND LEACH STOCKPILES

The components of inventories follow (in millions):

	September 30, 2015		December 31, 2014
Current inventories:
Total materials and supplies, neta	$	2,071	$	1,886
Mill stockpiles	$	118	$	86
Leach stockpiles	1,777		1,828
Total current mill and leach stockpiles	$	1,895	$	1,914
Raw materials (primarily concentrates)	$	281	$	288
Work-in-process	102		174
Finished goods	996		1,099
Total product inventories	$	1,379	$	1,561
Long-term inventories:
Mill stockpiles	$	444	$	360
Leach stockpiles	1,882		1,819
Total long-term mill and leach stockpilesb	$	2,326	$	2,179

a. Materials and supplies inventory was net of obsolescence reserves totaling $26 million at September 30, 2015, and $20 million at December 31, 2014.

b. Estimated metals in stockpiles not expected to be recovered within the next 12 months.

Beginning in third-quarter 2015, FCX adopted new accounting guidance for the subsequent measurement of inventories (refer to Note 12), which resulted in a change in accounting principle, whereby inventories are stated at the lower of weighted-average cost or net realizable value. Prior to third-quarter 2015, FCX's inventories were stated at the lower of weighted-average cost or market.

FCX recorded charges to production costs for adjustments to inventory carrying values of $91 million ($37 million for molybdenum inventories and $54 million for copper inventories) for third-quarter2015 and $154 million ($89 million for molybdenum inventories and $65 million for copper inventories) for the first nine months of 2015, primarily because of lower molybdenum and copper prices (refer to Note 10 for inventory adjustments by business segment).