# Relationship history for MSHA mine 3503591

Current hierarchy: **Art A  Schweizer → Green Diamond Sand Products → Arden Development**

- 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:** Green Diamond Sand Products → Arden Development; 2004-05-28 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Art A  Schweizer → Arden Development; 2004-05-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Art A  Schweizer → Green Diamond Sand Products; 2004-05-28 to current/open; source msha-controller-operator-history