LEASES: (Tables)

9 Months Ended

Sep. 30, 2021

LEASES:

Schedule of the operating lease expense recognized

The operating lease expense recognized in the first nine months of 2021 and 2020 was classified as follows (in millions):

Classification	2021		2020
Cost of sales (exclusive of depreciation, amortization and depletion)	$	85.8	$	86.4
Selling, general and administrative		0.1		0.2
Exploration		0.1		0.1
Total lease expense	$	86.0	$	86.7

Schedule of Maturities of lease liabilities

	Lease liabilities
Year	(in millions)
2021	$	28.6
2022		113.7
2023		112.4
2024		104.7
2025		103.7
After 2025		723.0
Total lease payments	$	1,186.1
Less: interest on lease liabilities		(259.5)
Present value of lease payments	$	926.6