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

6 Months Ended

Jun. 30, 2020

Inventory Disclosure [Abstract]

Schedule of Inventory

The components of inventories follow (in millions):

	June 30, 2020		December 31, 2019
Current inventories:
Total materials and supplies, neta	$	1,604	$	1,649
Mill stockpiles	$	166	$	220
Leach stockpiles	864		923
Total current mill and leach stockpiles	$	1,030	$	1,143
Raw materials (primarily concentrate)	$	287	$	318
Work-in-process	110		124
Finished goods	779		839
Total product	$	1,176	$	1,281
Long-term inventories:
Mill stockpiles	$	207	$	181
Leach stockpiles	1,239		1,244
Total long-term mill and leach stockpilesb	$	1,446	$	1,425

a. Materials and supplies inventory was net of obsolescence reserves totaling $31 million at June 30, 2020, and $24 million at December 31, 2019.

b.

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