Property, Plant and Equipment (Tables)

12 Months Ended

Dec. 31, 2024

Property, Plant and Equipment [Abstract]

Major Categories of Property, Plant and Equipment and Accumulated Depreciation and Depletion

The major categories of property, plant and equipment and accumulated depreciation and depletion are presented below:

	December 31,
(millions of dollars)	2024			2023
Mineral rights and reserves	$	560.0		$	552.6
Land		43.0			44.5
Buildings		202.0			207.3
Machinery and equipment		1,236.4			1,201.1
Furniture and fixtures and other		144.5			140.0
Construction in progress		50.7			44.6
		2,236.6			2,190.1
Less: accumulated depreciation and depletion		(1,246.9	)		(1,203.3	)
Property, plant and equipment, net	$	989.7		$	986.8