# Relationship history for MSHA mine 1102931

Current hierarchy: **Amrize Ltd → Amrize Mid-America Inc. → Amrize Conco Western Stone**

- 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:** Lyle C  Sitterly Jr → Amrize Conco Western Stone; 1950-01-01 to 2006-10-05; source msha-controller-operator-history
- **operator_operates_mine:** Lafarge Conco Western Inc → Amrize Conco Western Stone; 1992-09-01 to 2009-11-01; source msha-controller-operator-history
- **controller_controls_operator:** Lyle C  Sitterly Jr → Lafarge Conco Western Inc; 1992-09-01 to 2006-10-05; source msha-controller-operator-history
- **controller_controls_mine:** Lafarge S A → Amrize Conco Western Stone; 2006-10-06 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Lafarge S A → Lafarge Conco Western Inc; 2006-10-06 to 2009-11-01; source msha-controller-operator-history
- **controller_controls_mine:** Lafarge S A → Amrize Conco Western Stone; 2009-06-01 to 2015-07-09; source msha-controller-operator-history
- **operator_operates_mine:** Amrize Mid-America Inc. → Amrize Conco Western Stone; 2009-11-02 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Lafarge S A → Amrize Mid-America Inc.; 2009-11-02 to 2015-07-09; source msha-controller-operator-history
- **controller_controls_mine:** Holcim Ltd → Amrize Conco Western Stone; 2015-07-10 to 2025-06-22; source msha-controller-operator-history
- **controller_controls_operator:** Holcim Ltd → Amrize Mid-America Inc.; 2015-07-10 to 2025-06-22; source msha-controller-operator-history
- **controller_controls_mine:** Amrize Ltd → Amrize Conco Western Stone; 2025-06-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Amrize Ltd → Amrize Mid-America Inc.; 2025-06-23 to current/open; source msha-controller-operator-history