INVENTORIES, INCLUDING LONG-TERM MILL AND LEACH STOCKPILES (Tables)

12 Months Ended

Dec. 31, 2019

Inventory Disclosure [Abstract]

Components of Inventories

The components of inventories follow:

	December 31,
	2019		2018
Current inventories:
Total materials and supplies, neta	$	1,649	$	1,528
Mill stockpiles	$	220	$	282
Leach stockpiles	923		915		b
Total current mill and leach stockpiles	$	1,143	$	1,197	b
Raw materials (primarily concentrate)	$	318	$	260
Work-in-process	124		192
Finished goods	839		1,326
Total product	$	1,281	$	1,778
Long-term inventories:
Mill stockpiles	$	181	$	265
Leach stockpiles	1,244		1,305		b
Total long-term mill and leach stockpilesc	$	1,425	$	1,570	b

a. Materials and supplies inventory was net of obsolescence reserves totaling $24 million at December 31, 2019 and 2018.

b. In fourth-quarter 2019, FCX changed its method of estimating the current portion of its leach stockpiles and revised its December 31, 2018, balances to conform with the new methodology resulting in a $256 million decrease in the current balance and a corresponding increase in the long-term balance.

c.

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