# Relationship history for MSHA mine 2901937

Current hierarchy: **Grainger James R → Ivanhoe Emporia Mines → Ivanhoe**

- 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:** Mimbres Resources Development Company Ltd → Ivanhoe; 1983-09-01 to 1988-05-17; source msha-controller-operator-history
- **controller_controls_mine:** Lozelle T → Ivanhoe; 1983-09-01 to 1988-05-17; source msha-controller-operator-history
- **controller_controls_operator:** Lozelle T → Mimbres Resources Development Company Ltd; 1983-09-01 to 1988-05-17; source msha-controller-operator-history
- **operator_operates_mine:** Ivanhoe Emporia Mines → Ivanhoe; 1988-05-18 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Grainger James R → Ivanhoe; 1988-05-18 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Grainger James R → Ivanhoe Emporia Mines; 1988-05-18 to current/open; source msha-controller-operator-history