# Relationship history for MSHA mine 4403896

Current hierarchy: **Blackstone Mining Corp → R & R Coal Company → No 1 Strip**

- 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:** R & R Coal Company → No 1 Strip; 1950-01-01 to 1977-08-03; source msha-controller-operator-history
- **controller_controls_mine:** Mullins Ronald G → No 1 Strip; 1950-01-01 to 1977-08-03; source msha-controller-operator-history
- **controller_controls_operator:** Mullins Ronald G → R & R Coal Company; 1950-01-01 to 1977-08-03; source msha-controller-operator-history
- **operator_operates_mine:** R & R Coal Company → No 1 Strip; 1977-08-04 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Blackstone Mining Corp → No 1 Strip; 1977-08-04 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Blackstone Mining Corp → R & R Coal Company; 1977-08-04 to current/open; source msha-controller-operator-history