# Relationship history for MSHA mine 1512247

Current hierarchy: **Cyprus Amax Minerals Company → Brownies Creek Collieries Inc → Last Chance**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **controller_controls_mine:** Harbert Construction Corp → Last Chance; 1976-08-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Brownies Creek Collieries Inc → Last Chance; 1980-03-01 to 1981-09-30; source msha-controller-operator-history
- **controller_controls_operator:** Harbert Construction Corp → Brownies Creek Collieries Inc; 1980-03-01 to 1981-09-30; source msha-controller-operator-history
- **controller_controls_mine:** Cyprus Amax Minerals Company → Last Chance; 1981-06-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Brownies Creek Collieries Inc → Last Chance; 1981-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Cyprus Amax Minerals Company → Brownies Creek Collieries Inc; 1981-10-01 to current/open; source msha-controller-operator-history