# Relationship history for MSHA mine 0900853

Current hierarchy: **Black Don → Mineral Extractors Inc → Mineral No 3 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:** Black Don → Mineral No 3 Strip; 1976-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Morcoal Inc → Mineral No 3 Strip; 1976-10-01 to 1977-06-20; source msha-controller-operator-history
- **controller_controls_mine:** Morrow J P → Mineral No 3 Strip; 1976-10-01 to 1977-06-20; source msha-controller-operator-history
- **controller_controls_operator:** Morrow J P → Morcoal Inc; 1976-10-01 to 1977-06-20; source msha-controller-operator-history
- **operator_operates_mine:** Mineral Extractors Inc → Mineral No 3 Strip; 1977-06-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Black Don → Mineral Extractors Inc; 1977-06-21 to current/open; source msha-controller-operator-history