# Relationship history for MSHA mine 0504471

Current hierarchy: **Aggregate Industries PLC → Camas Colorado Inc → BRIGHTON PLANT**

- 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:** English China Clays PLC → BRIGHTON PLANT; 1988-07-19 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Cooley Gravel Company → BRIGHTON PLANT; 1991-10-01 to 1994-07-31; source msha-controller-operator-history
- **controller_controls_operator:** English China Clays PLC → Cooley Gravel Company; 1991-10-01 to 1994-07-31; source msha-controller-operator-history
- **operator_operates_mine:** Cooley Gravel Company → BRIGHTON PLANT; 1994-08-01 to 1997-05-13; source msha-controller-operator-history
- **controller_controls_mine:** Camas Plc → BRIGHTON PLANT; 1994-08-01 to 1997-05-13; source msha-controller-operator-history
- **controller_controls_operator:** Camas Plc → Cooley Gravel Company; 1994-08-01 to 1997-05-13; source msha-controller-operator-history
- **operator_operates_mine:** Camas Colorado Inc → BRIGHTON PLANT; 1997-05-14 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Aggregate Industries PLC → BRIGHTON PLANT; 1997-05-14 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Aggregate Industries PLC → Camas Colorado Inc; 1997-05-14 to current/open; source msha-controller-operator-history