# Relationship history for MSHA mine 2601433

Current hierarchy: **Mear Lloyd E → Desert Refining Inc → Tungsten Mountain Mill**

- 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:** Farmers Exchange Of Modoc Inc → Tungsten Mountain Mill; 1950-01-01 to 1983-09-18; source msha-controller-operator-history
- **controller_controls_mine:** Koza Don → Tungsten Mountain Mill; 1950-01-01 to 1985-05-04; source msha-controller-operator-history
- **controller_controls_operator:** Koza Don → Farmers Exchange Of Modoc Inc; 1950-01-01 to 1983-09-18; source msha-controller-operator-history
- **operator_operates_mine:** Desert Refining Inc → Tungsten Mountain Mill; 1983-09-19 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Mear Lloyd E → Tungsten Mountain Mill; 1983-09-19 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mear Lloyd E → Desert Refining Inc; 1983-09-19 to current/open; source msha-controller-operator-history