# Relationship history for MSHA mine 0401787

Current hierarchy: **Salud Maria  Gordon → Gordon Sand Co → Gordon Sand Co**

- 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:** Gordon Sand Co → Gordon Sand Co; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** George E  Gordon III → Gordon Sand Co; 1950-01-01 to 2017-08-11; source msha-controller-operator-history
- **controller_controls_operator:** George E  Gordon III → Gordon Sand Co; 1950-01-01 to 2017-08-11; source msha-controller-operator-history
- **controller_controls_mine:** Salud Maria  Gordon → Gordon Sand Co; 2017-08-12 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Salud Maria  Gordon → Gordon Sand Co; 2017-08-12 to current/open; source msha-controller-operator-history