# Relationship history for MSHA mine 3503241

Current hierarchy: **John B  Dalton → Dalton Rock Inc → Dalton 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:** Agate Rock & Redi Mix Company → Dalton Quarry; 1985-08-01 to 1995-02-08; source msha-controller-operator-history
- **controller_controls_mine:** Ralph L  Dick  et al → Dalton Quarry; 1985-08-01 to 1995-02-08; source msha-controller-operator-history
- **controller_controls_operator:** Ralph L  Dick  et al → Agate Rock & Redi Mix Company; 1985-08-01 to 1995-02-08; source msha-controller-operator-history
- **operator_operates_mine:** Dalton Rock Inc → Dalton Quarry; 1995-02-09 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** John B  Dalton → Dalton Quarry; 1995-02-09 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** John B  Dalton → Dalton Rock Inc; 1995-02-09 to current/open; source msha-controller-operator-history