# Relationship history for MSHA mine 2601469

Current hierarchy: **Chandler L & R E Nelson → Silverhorn Research Mill Inc → Silverhorn 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

- **operator_operates_mine:** Silverhorn Research Mill Inc → Silverhorn Mine; 1978-03-09 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Chandler L & R E Nelson → Silverhorn Mine; 1978-03-09 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Chandler L & R E Nelson → Silverhorn Research Mill Inc; 1978-03-09 to current/open; source msha-controller-operator-history