# Relationship history for MSHA mine 1502257

Current hierarchy: **Goldfield Corp → Harlan Fuel Company → Elzo No 4 Mine**

- 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:** Harlan Fuel Company → Elzo No 4 Mine; 1950-01-01 to 1975-03-12; source msha-controller-operator-history
- **controller_controls_mine:** Bennett Clyde V → Elzo No 4 Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bennett Clyde V → Harlan Fuel Company; 1950-01-01 to 1975-03-12; source msha-controller-operator-history
- **operator_operates_mine:** Harlan Fuel Company → Elzo No 4 Mine; 1975-03-13 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Goldfield Corp → Elzo No 4 Mine; 1975-03-13 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Goldfield Corp → Harlan Fuel Company; 1975-03-13 to current/open; source msha-controller-operator-history