# Relationship history for MSHA mine 1201150

Current hierarchy: **Heidelberg Materials AG → Heidelberg Materials Midwest Agg, Inc. → HARDING STREET QUARRY-SURFACE**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** American Aggregates Corp → HARDING STREET QUARRY-SURFACE; 1950-01-01 to 1987-02-28; source msha-controller-operator-history
- **controller_controls_mine:** American Aggregates Corp → HARDING STREET QUARRY-SURFACE; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** American Aggregates Corp → American Aggregates Corp; 1950-01-01 to 1987-02-28; source msha-controller-operator-history
- **controller_controls_mine:** Martin Marietta Materials Inc → HARDING STREET QUARRY-SURFACE; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Consolidated Gold Fields Limited → HARDING STREET QUARRY-SURFACE; 1987-02-04 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** American Aggregates Corp → HARDING STREET QUARRY-SURFACE; 1987-03-01 to 1989-08-09; source msha-controller-operator-history
- **controller_controls_operator:** Consolidated Gold Fields Limited → American Aggregates Corp; 1987-03-01 to 1989-08-09; source msha-controller-operator-history
- **controller_controls_mine:** Hanson PLC → HARDING STREET QUARRY-SURFACE; 1988-11-14 to 2007-08-22; source msha-controller-operator-history
- **controller_controls_mine:** Hanson PLC → HARDING STREET QUARRY-SURFACE; 1989-03-10 to 1990-02-01; source msha-controller-operator-history
- **operator_operates_mine:** American Aggregates Corp → HARDING STREET QUARRY-SURFACE; 1989-08-10 to 1990-02-01; source msha-controller-operator-history
- **controller_controls_operator:** Hanson PLC → American Aggregates Corp; 1989-08-10 to 1990-02-01; source msha-controller-operator-history
- **operator_operates_mine:** American Aggregates Corp → HARDING STREET QUARRY-SURFACE; 1990-02-02 to 1997-05-27; source msha-controller-operator-history
- **controller_controls_mine:** CSR Ltd → HARDING STREET QUARRY-SURFACE; 1990-02-02 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** CSR Ltd → American Aggregates Corp; 1990-02-02 to 1997-05-27; source msha-controller-operator-history
- **operator_operates_mine:** Martin Marietta Aggregates → HARDING STREET QUARRY-SURFACE; 1997-05-28 to 1998-01-18; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Martin Marietta Aggregates; 1997-05-28 to 1998-01-18; source msha-controller-operator-history
- **operator_operates_mine:** Heidelberg Materials Midwest Agg, Inc. → HARDING STREET QUARRY-SURFACE; 1998-01-19 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hanson PLC → Heidelberg Materials Midwest Agg, Inc.; 1998-01-19 to 2007-08-22; source msha-controller-operator-history
- **controller_controls_mine:** Heidelberg Materials AG → HARDING STREET QUARRY-SURFACE; 2007-08-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Heidelberg Materials AG → Heidelberg Materials Midwest Agg, Inc.; 2007-08-23 to current/open; source msha-controller-operator-history