# Relationship history for MSHA mine 0102457

Current hierarchy: **Rogers John F Jr → Buckhorn Processing Company → Arnold Mine**

- 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:** Quick Hershel A → Arnold Mine; 1977-06-01 to 1983-09-12; source msha-controller-operator-history
- **operator_operates_mine:** Q & R Coal Company Inc → Arnold Mine; 1982-03-01 to 1983-06-30; source msha-controller-operator-history
- **controller_controls_operator:** Quick Hershel A → Q & R Coal Company Inc; 1982-03-01 to 1983-06-30; source msha-controller-operator-history
- **operator_operates_mine:** Buckhorn Processing Company → Arnold Mine; 1983-07-01 to 1984-06-28; source msha-controller-operator-history
- **controller_controls_mine:** Rogers John F Jr → Arnold Mine; 1983-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Rogers John F Jr → Buckhorn Processing Company; 1983-07-01 to 1984-06-28; source msha-controller-operator-history
- **operator_operates_mine:** Bullock Mining Company Inc → Arnold Mine; 1984-06-29 to 1984-09-26; source msha-controller-operator-history
- **controller_controls_mine:** Frank C  Mann → Arnold Mine; 1984-06-29 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Frank C  Mann → Bullock Mining Company Inc; 1984-06-29 to 1984-09-26; source msha-controller-operator-history
- **operator_operates_mine:** Buckhorn Processing Company → Arnold Mine; 1984-09-27 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Rogers John F Jr → Buckhorn Processing Company; 1984-09-27 to current/open; source msha-controller-operator-history