# Relationship history for MSHA mine 1800450

Current hierarchy: **Cowl Energy Corp → New Mineral Coal Company Inc → No 1 Strip**

- 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

- **controller_controls_mine:** Grafton Coal Company → No 1 Strip; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Fitzwater C Ernest → No 1 Strip; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Grafton Coal Company → No 1 Strip; 1973-01-01 to 1973-12-31; source msha-controller-operator-history
- **controller_controls_operator:** Grafton Coal Company → Grafton Coal Company; 1973-01-01 to 1973-12-31; source msha-controller-operator-history
- **operator_operates_mine:** Mineral Coal Company Inc Of W Va → No 1 Strip; 1974-01-01 to 1974-10-27; source msha-controller-operator-history
- **controller_controls_operator:** Fitzwater C Ernest → Mineral Coal Company Inc Of W Va; 1974-01-01 to 1974-10-27; source msha-controller-operator-history
- **operator_operates_mine:** New Mineral Coal Company Inc → No 1 Strip; 1974-10-28 to 1978-04-13; source msha-controller-operator-history
- **controller_controls_mine:** Mc Call-John Coal Company Inc → No 1 Strip; 1974-10-28 to 1978-04-13; source msha-controller-operator-history
- **controller_controls_operator:** Mc Call-John Coal Company Inc → New Mineral Coal Company Inc; 1974-10-28 to 1978-04-13; source msha-controller-operator-history
- **operator_operates_mine:** New Mineral Coal Company Inc → No 1 Strip; 1978-04-14 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Cowl Energy Corp → No 1 Strip; 1978-04-14 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Cowl Energy Corp → New Mineral Coal Company Inc; 1978-04-14 to current/open; source msha-controller-operator-history