# Relationship history for MSHA mine 3100678

Current hierarchy: **Covia Holdings LLC → Unimin Corp → PLANT #1**

- 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:** International Minerals & Chemical Corp → PLANT #1; 1950-01-01 to 1986-10-31; source msha-controller-operator-history
- **controller_controls_mine:** IMC Global Inc → PLANT #1; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** IMC Global Inc → International Minerals & Chemical Corp; 1950-01-01 to 1986-10-31; source msha-controller-operator-history
- **controller_controls_mine:** S C R-Sibelco Nv et al → PLANT #1; 1950-01-01 to 2020-12-31; source msha-controller-operator-history
- **operator_operates_mine:** Applied Industrial Materials Corp (Aimcor) → PLANT #1; 1986-11-01 to 1994-05-01; source msha-controller-operator-history
- **controller_controls_mine:** Charles  Gallagher et al → PLANT #1; 1986-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Charles  Gallagher et al → Applied Industrial Materials Corp (Aimcor); 1986-11-01 to 1994-05-01; source msha-controller-operator-history
- **operator_operates_mine:** Unimin Corp → PLANT #1; 1994-05-02 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** S C R-Sibelco Nv et al → Unimin Corp; 1994-05-02 to 2020-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Covia Holdings LLC → PLANT #1; 2021-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Covia Holdings LLC → Unimin Corp; 2021-01-01 to current/open; source msha-controller-operator-history