# Relationship history for MSHA mine 1001768

Current hierarchy: **Carl A  Register → Carco Mineral Resources Inc → Caldwell Plant**

- 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

- **controller_controls_mine:** S C R-Sibelco Nv et al → Caldwell Plant; 1950-01-01 to 2020-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Charles  Gallagher et al → Caldwell Plant; 1986-11-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Applied Industrial Materials Corp (Aimcor) → Caldwell Plant; 1986-12-01 to 1994-04-28; source msha-controller-operator-history
- **controller_controls_operator:** Charles  Gallagher et al → Applied Industrial Materials Corp (Aimcor); 1986-12-01 to 1994-04-28; source msha-controller-operator-history
- **operator_operates_mine:** Unimin Corp → Caldwell Plant; 1994-04-29 to 1995-12-28; source msha-controller-operator-history
- **controller_controls_operator:** S C R-Sibelco Nv et al → Unimin Corp; 1994-04-29 to 1995-12-28; source msha-controller-operator-history
- **operator_operates_mine:** Carco Mineral Resources Inc → Caldwell Plant; 1995-12-29 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Carl A  Register → Caldwell Plant; 1995-12-29 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Carl A  Register → Carco Mineral Resources Inc; 1995-12-29 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Covia Holdings LLC → Caldwell Plant; 2021-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Covia Holdings LLC → Unimin Corp; 2021-01-01 to 1995-12-28; source msha-controller-operator-history