# Relationship history for MSHA mine 0500964

Current hierarchy: **English China Clays PLC → Cooley Gravel Company → Littleton 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

- **operator_operates_mine:** Cooley Gravel Company → Littleton Plant; 1950-01-01 to 1988-07-18; source msha-controller-operator-history
- **controller_controls_mine:** J L Shiely  Company → Littleton Plant; 1950-01-01 to 1988-07-18; source msha-controller-operator-history
- **controller_controls_operator:** J L Shiely  Company → Cooley Gravel Company; 1950-01-01 to 1988-07-18; source msha-controller-operator-history
- **operator_operates_mine:** Cooley Gravel Company → Littleton Plant; 1988-07-19 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** English China Clays PLC → Littleton Plant; 1988-07-19 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** English China Clays PLC → Cooley Gravel Company; 1988-07-19 to current/open; source msha-controller-operator-history