Company: NC
Filing Date: 2025-03-05
Form Type: 10-K
Source: 0000789933-25-000006
Chunk: 97

Company: NACCO INDUSTRIES INC
Filing Date: 2025-03-05
Form: 10-K
Item: Item 2
Chunk 97
---
 of $34.40 per ton at MLMC.

Material assumptions and criteria used in the determination of Mineral Resource and Mineral Reserves reported herein are provided within the filed TRS for the MLMC – Red Hills Mine dated December 31, 2024.

Section 11.0 of the TRS describes the key assumptions, parameters, and methods used for the estimation of Mineral Resources. Assumptions include a maximum cumulative stripping ratio of 18:1 based on an assumed lignite sales price of $34.02 per ton. A further description of the verified drilling data used to model the lignite deposit for estimation of Mineral Resources is provided in Section 7.2 Drilling Exploration, 8.0 Sample Preparation, Analyses, and Security, and Section 9.0 Data Verification.

Section 12.0 of the TRS describes the key assumptions, parameters, and methods used for the estimation of Mineral Reserves, and include the following:

•Maximum stripping ratio: 14:1;

•Mining production rates on a cubic yard and per ton basis remain relatively consistent with historical performance;

•Mining costs on a unit basis remain relatively consistent with historical performance;

•Minimum minable lignite thickness: 1.0 feet;

•Minimum parting thickness before seams are composited: 6.0 inches;

•Maximum depth of mining: approximately 320 feet;

•Lignite density defined by seam from coal core drilling data and modified by dilution parameters and approximately 80 lb/ft³; and

•Recovery rates by seam ranging from 67% to 100%. 

Modifying factors including dilution parameters and technical information related to the mining process are described in detail under Section 13.0 Mining Methods. Economic factors to support the Mineral Reserve estimates are described in Section 18.0 Capital and Operating Costs and 19.0 Economic Analyses.

The Mineral Resources as of December 31, 2024 presented in Table 2.2 below have been estimated by applying a series of geologic and physical limits as well as high-level mining and economic constraints. The mining and economic constraints were limited to a level sufficient to support reasonable prospect for future economic extraction of the estimated Mineral Resources.  The categorized Mineral Resources reported herein are exclusive of Mineral Reserves.

Lignite CoalResource ClassificationTonnage( Kt)Grades/QualitiesCalorific Value (Btu/lb)Moisture (%wt)Ash (%wt)Sulfur (%wt)Mississippi Lignite Mining Company