# Relationship history for MSHA mine 1600812

Current hierarchy: **Chromalloy American Corp → Chromalloy Mining & Milling → Barite Plant No 1 Or No 2**

- 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:** Chromalloy Mining & Milling → Barite Plant No 1 Or No 2; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Chromalloy American Corp → Barite Plant No 1 Or No 2; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Chromalloy American Corp → Chromalloy Mining & Milling; 1950-01-01 to current/open; source msha-controller-operator-history