# Relationship history for MSHA mine 3302429

Current hierarchy: **CONSOL Energy Inc → Quarto Mining Company → Central Shop**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** North American Coal Corp → Central Shop; 1950-01-01 to 1987-04-10; source msha-controller-operator-history
- **controller_controls_mine:** NACCO Industries Inc → Central Shop; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** NACCO Industries Inc → North American Coal Corp; 1950-01-01 to 1987-04-10; source msha-controller-operator-history
- **operator_operates_mine:** Quarto Mining Company → Central Shop; 1987-04-11 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** CONSOL Energy Inc → Central Shop; 1987-04-11 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** CONSOL Energy Inc → Quarto Mining Company; 1987-04-11 to current/open; source msha-controller-operator-history