# Relationship history for MSHA mine 3304530

Current hierarchy: **John F. Gradel Sr Trust → Geo Gradel Co → Marblehead 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

- **operator_operates_mine:** Geo Gradel Co → Marblehead Quarry; 2004-05-03 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** John F  Gradel Sr → Marblehead Quarry; 2004-05-03 to 2023-04-19; source msha-controller-operator-history
- **controller_controls_operator:** John F  Gradel Sr → Geo Gradel Co; 2004-05-03 to 2023-04-19; source msha-controller-operator-history
- **controller_controls_mine:** John F. Gradel Sr Trust → Marblehead Quarry; 2023-04-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** John F. Gradel Sr Trust → Geo Gradel Co; 2023-04-20 to current/open; source msha-controller-operator-history