# Relationship history for MSHA mine 1400842

Current hierarchy: **Willene  Nelson → R W Nelson Quarries → Yates Center Quarry & Mill Or Yates Cent**

- 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:** R W Nelson Quarries → Yates Center Quarry & Mill Or Yates Cent; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Willene  Nelson → Yates Center Quarry & Mill Or Yates Cent; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Willene  Nelson → R W Nelson Quarries; 1950-01-01 to current/open; source msha-controller-operator-history