# Relationship history for MSHA mine 4600007

Current hierarchy: **Quikrete Holdings Inc. → Quikrete Construction Materials, LLC → Martinsburg**

- 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:** Martin Marietta Cement → Martinsburg; 1950-01-01 to 1984-03-13; source msha-controller-operator-history
- **controller_controls_mine:** Martin Marietta Materials Inc → Martinsburg; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Martin Marietta Cement; 1950-01-01 to 1984-03-13; source msha-controller-operator-history
- **operator_operates_mine:** Capitol Cement Corp → Martinsburg; 1984-03-14 to 2003-08-20; source msha-controller-operator-history
- **controller_controls_mine:** Capitol Materials Corporation → Martinsburg; 1984-03-14 to 2002-05-20; source msha-controller-operator-history
- **controller_controls_operator:** Capitol Materials Corporation → Capitol Cement Corp; 1984-03-14 to 2002-05-20; source msha-controller-operator-history
- **controller_controls_mine:** Italcementi Spa → Martinsburg; 2002-05-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Italcementi Spa → Capitol Cement Corp; 2002-05-21 to 2003-08-20; source msha-controller-operator-history
- **operator_operates_mine:** Essroc Cement Corp. → Martinsburg; 2003-08-21 to 2016-11-30; source msha-controller-operator-history
- **controller_controls_mine:** Italcementi Spa → Martinsburg; 2003-08-21 to 2016-10-11; source msha-controller-operator-history
- **controller_controls_operator:** Italcementi Spa → Essroc Cement Corp.; 2003-08-21 to 2016-10-11; source msha-controller-operator-history
- **controller_controls_mine:** Cementos Argos S A → Martinsburg; 2011-10-03 to 2023-01-11; source msha-controller-operator-history
- **controller_controls_mine:** Heidelberg Materials AG → Martinsburg; 2016-10-12 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Heidelberg Materials AG → Essroc Cement Corp.; 2016-10-12 to 2016-11-30; source msha-controller-operator-history
- **operator_operates_mine:** Quikrete Construction Materials, LLC → Martinsburg; 2016-12-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Cementos Argos S A → Quikrete Construction Materials, LLC; 2016-12-01 to 2023-01-11; source msha-controller-operator-history
- **controller_controls_mine:** Summit Materials LLC → Martinsburg; 2023-01-12 to 2025-08-03; source msha-controller-operator-history
- **controller_controls_operator:** Summit Materials LLC → Quikrete Construction Materials, LLC; 2023-01-12 to 2025-08-03; source msha-controller-operator-history
- **controller_controls_mine:** Quikrete Holdings Inc. → Martinsburg; 2025-08-04 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Quikrete Holdings Inc. → Quikrete Construction Materials, LLC; 2025-08-04 to current/open; source msha-controller-operator-history