# Relationship history for MSHA mine 1102057

Current hierarchy: **Charles  Hammersmith Jr → Elmhurst-Chicago Stone → Plainfield Plant**

- 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:** Elmhurst-Chicago Stone → Plainfield Plant; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Charles  Hammersmith Jr → Plainfield Plant; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Charles  Hammersmith Jr → Elmhurst-Chicago Stone; 1950-01-01 to current/open; source msha-controller-operator-history