# Relationship history for MSHA mine 2601768

Current hierarchy: **Andersen Eric → Placer Management Group Ltd → Placer-Goldfield**

- 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

- **operator_operates_mine:** Blackhawk Mines Corp → Placer-Goldfield; 1981-09-01 to 1986-06-24; source msha-controller-operator-history
- **controller_controls_mine:** Amax Exploration--Pacific Gold & Uranium Inc Et Al → Placer-Goldfield; 1981-09-01 to 1986-06-24; source msha-controller-operator-history
- **controller_controls_operator:** Amax Exploration--Pacific Gold & Uranium Inc Et Al → Blackhawk Mines Corp; 1981-09-01 to 1986-06-24; source msha-controller-operator-history
- **operator_operates_mine:** Placer Management Group Ltd → Placer-Goldfield; 1986-06-25 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Andersen Eric → Placer-Goldfield; 1986-06-25 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Andersen Eric → Placer Management Group Ltd; 1986-06-25 to current/open; source msha-controller-operator-history