# Relationship history for MSHA mine 0500213

Current hierarchy: **Johnston Delbert F → Red Mountain Clay → Cedarwood Pit**

- 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

- **controller_controls_mine:** Joseph C  Welte et al → Cedarwood Pit; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Red Mountain Clay → Cedarwood Pit; 1950-01-01 to 1984-01-23; source msha-controller-operator-history
- **controller_controls_mine:** Johnston Delbert F → Cedarwood Pit; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Johnston Delbert F → Red Mountain Clay; 1950-01-01 to 1984-01-23; source msha-controller-operator-history
- **operator_operates_mine:** Summit Pressed Brick & Tile Company → Cedarwood Pit; 1984-01-24 to 1986-01-15; source msha-controller-operator-history
- **controller_controls_operator:** Joseph C  Welte et al → Summit Pressed Brick & Tile Company; 1984-01-24 to 1986-01-15; source msha-controller-operator-history
- **operator_operates_mine:** Red Mountain Clay → Cedarwood Pit; 1986-01-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Johnston Delbert F → Red Mountain Clay; 1986-01-16 to current/open; source msha-controller-operator-history