# Relationship history for MSHA mine 0405310

Current hierarchy: **Calvin E  Vance → Vance Corp → PYRITE QUARRY**

- 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:** Calvin E  Vance → PYRITE QUARRY; 1991-03-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Vance Corp → PYRITE QUARRY; 1997-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Calvin E  Vance → Vance Corp; 1997-05-01 to current/open; source msha-controller-operator-history