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v3.25.1

COMPONENTS OF PENSION PLAN NET PERIODIC BENEFIT COSTS | 3 Months Ended
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Mar. 31, 2025
COMPONENTS OF PENSION PLAN NET PERIODIC BENEFIT COSTS |
COMPONENTS OF PENSION PLAN NET PERIODIC BENEFIT COSTS | 10.COMPONENTS OF PENSION PLAN NET PERIODIC BENEFIT COSTS ​ Eligible employees at certain of our mining operations participate in a defined benefit plan (the “Pension Plan”) that we sponsor. The Pension Plan is currently closed to new applicants and participants in the Pension Plan are no longer receiving benefit accruals for service. The benefit formula for the Pension Plan is a fixed dollar unit based on years of service. Components of the net periodic benefit credit for each of the periods presented are as follows: ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ |  | Three Months Ended | ​
​ | ​ | March 31, | ​
​ | ​ | 2025 |  | 2024 |
​ | ​ | (in thousands) | ​
Interest cost | ​ | $ | 1,310 | ​ | $ | 1,259 | ​
Expected return on plan assets | ​ |  | (1,709) | ​ |  | (1,765) | ​
Amortization of prior service cost | ​ | ​ | 3 | ​ | ​ | 47 | ​
Amortization of net loss | ​ |  | — | ​ |  | 37 | ​
Net periodic benefit credit (1) | ​ | $ | (396) | ​ | $ | (422) | ​
| (1) | Net periodic benefit credit for the Pension Plan is included in the Other income (expense) line item within our condensed consolidated statements of income.
​ We do not expect to make material contributions to the Pension Plan during 2025.

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