# Relationship history for MSHA mine 0503572

Current hierarchy: **Sharp James E & Lawrence Barker → Draco Gold Mines Inc → Crystal Hill**

- 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:** Crystal Hill Mining Company-Draco Mines → Crystal Hill; 1980-09-01 to 1987-07-08; source msha-controller-operator-history
- **controller_controls_mine:** Southern Cross Ltd → Crystal Hill; 1980-09-01 to 1987-07-08; source msha-controller-operator-history
- **controller_controls_operator:** Southern Cross Ltd → Crystal Hill Mining Company-Draco Mines; 1980-09-01 to 1987-07-08; source msha-controller-operator-history
- **operator_operates_mine:** Draco Gold Mines Inc → Crystal Hill; 1987-07-09 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Sharp James E & Lawrence Barker → Crystal Hill; 1987-07-09 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Sharp James E & Lawrence Barker → Draco Gold Mines Inc; 1987-07-09 to current/open; source msha-controller-operator-history