# Relationship history for MSHA mine 1400699

Current hierarchy: **CRH PLC → Apac-Kansas Inc  Shears Division → QUARTZITE QUARRY**

- 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:** Ashland Inc → QUARTZITE QUARRY; 1950-01-01 to 2006-08-27; source msha-controller-operator-history
- **operator_operates_mine:** Quartzite Stone Company Inc → QUARTZITE QUARRY; 1950-01-01 to 1984-06-19; source msha-controller-operator-history
- **controller_controls_mine:** Rex W  Ryan → QUARTZITE QUARRY; 1950-01-01 to 1984-06-20; source msha-controller-operator-history
- **controller_controls_operator:** Rex W  Ryan → Quartzite Stone Company Inc; 1950-01-01 to 1984-06-19; source msha-controller-operator-history
- **operator_operates_mine:** Quartzite Stone Company Inc → QUARTZITE QUARRY; 1984-06-20 to 1988-12-28; source msha-controller-operator-history
- **controller_controls_mine:** William  Shears Jr → QUARTZITE QUARRY; 1984-06-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** William  Shears Jr → Quartzite Stone Company Inc; 1984-06-20 to 1988-12-28; source msha-controller-operator-history
- **operator_operates_mine:** Couch Construction Materials → QUARTZITE QUARRY; 1988-12-29 to 2000-02-21; source msha-controller-operator-history
- **controller_controls_mine:** Superfos America Inc → QUARTZITE QUARRY; 1988-12-29 to 2000-02-21; source msha-controller-operator-history
- **controller_controls_operator:** Superfos America Inc → Couch Construction Materials; 1988-12-29 to 2000-02-21; source msha-controller-operator-history
- **operator_operates_mine:** Apac-Kansas Inc  Shears Division → QUARTZITE QUARRY; 2000-02-22 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ashland Inc → Apac-Kansas Inc  Shears Division; 2000-02-22 to 2006-08-27; source msha-controller-operator-history
- **controller_controls_mine:** CRH PLC → QUARTZITE QUARRY; 2006-08-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** CRH PLC → Apac-Kansas Inc  Shears Division; 2006-08-28 to current/open; source msha-controller-operator-history