# Relationship history for MSHA mine 1900469

Current hierarchy: **CRH PLC → Callanan Industries Inc → Pittsfield Sand and Gravel Inc**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **operator_operates_mine:** Vincent Sand & Gravel Inc → Pittsfield Sand and Gravel Inc; 1950-01-01 to 1981-06-08; source msha-controller-operator-history
- **controller_controls_mine:** James E  Vincent → Pittsfield Sand and Gravel Inc; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** James E  Vincent → Vincent Sand & Gravel Inc; 1950-01-01 to 1981-06-08; source msha-controller-operator-history
- **operator_operates_mine:** Pittsfield Sand & Gravel Inc → Pittsfield Sand and Gravel Inc; 1981-06-09 to 2008-01-13; source msha-controller-operator-history
- **controller_controls_mine:** Joseph N.  Kroboth → Pittsfield Sand and Gravel Inc; 1981-06-09 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Joseph N.  Kroboth → Pittsfield Sand & Gravel Inc; 1981-06-09 to 2008-01-13; source msha-controller-operator-history
- **controller_controls_mine:** CRH PLC → Pittsfield Sand and Gravel Inc; 1985-04-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Callanan Industries Inc → Pittsfield Sand and Gravel Inc; 2008-01-14 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** CRH PLC → Callanan Industries Inc; 2008-01-14 to current/open; source msha-controller-operator-history