# Relationship history for MSHA mine 1000791

Current hierarchy: **CRH PLC → Interstate Concrete & Asphalt Company → Newport**

- 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:** Newport Concrete Inc → Newport; 1950-01-01 to 1987-02-09; source msha-controller-operator-history
- **controller_controls_mine:** Clark David H → Newport; 1950-01-01 to 1987-02-09; source msha-controller-operator-history
- **controller_controls_operator:** Clark David H → Newport Concrete Inc; 1950-01-01 to 1987-02-09; source msha-controller-operator-history
- **operator_operates_mine:** Newport Concrete Inc → Newport; 1987-02-10 to 1990-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Jones Mary Ann → Newport; 1987-02-10 to 1990-12-31; source msha-controller-operator-history
- **controller_controls_operator:** Jones Mary Ann → Newport Concrete Inc; 1987-02-10 to 1990-12-31; source msha-controller-operator-history
- **controller_controls_mine:** CRH PLC → Newport; 1987-09-18 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Interstate Concrete & Asphalt Company → Newport; 1991-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** CRH PLC → Interstate Concrete & Asphalt Company; 1991-01-01 to current/open; source msha-controller-operator-history