# Relationship history for MSHA mine 3900902

Current hierarchy: **Cyprus Amax Minerals Company → Cyprus Exploration Company → Gilt Edge Mine**

- 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:** Strawberry Hill Mining Company Inc → Gilt Edge Mine; 1950-01-01 to 1980-06-03; source msha-controller-operator-history
- **controller_controls_mine:** Hoffman Maurice → Gilt Edge Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hoffman Maurice → Strawberry Hill Mining Company Inc; 1950-01-01 to 1980-06-03; source msha-controller-operator-history
- **operator_operates_mine:** Cyprus Exploration Company → Gilt Edge Mine; 1980-06-04 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Cyprus Amax Minerals Company → Gilt Edge Mine; 1980-06-04 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Cyprus Amax Minerals Company → Cyprus Exploration Company; 1980-06-04 to current/open; source msha-controller-operator-history