# Relationship history for MSHA mine 0404846

Current hierarchy: **Hanson PLC → Beazer West Of California Incorported → Crystal Hills Sand & Gravel Company**

- 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:** Crystal Hills Sand & Gravel Company Inc → Crystal Hills Sand & Gravel Company; 1986-11-01 to 1989-12-21; source msha-controller-operator-history
- **controller_controls_mine:** Pinkus Anita → Crystal Hills Sand & Gravel Company; 1986-11-01 to 1989-12-21; source msha-controller-operator-history
- **controller_controls_operator:** Pinkus Anita → Crystal Hills Sand & Gravel Company Inc; 1986-11-01 to 1989-12-21; source msha-controller-operator-history
- **operator_operates_mine:** Beazer West Of California Incorported → Crystal Hills Sand & Gravel Company; 1989-12-22 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Hanson PLC → Crystal Hills Sand & Gravel Company; 1989-12-22 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hanson PLC → Beazer West Of California Incorported; 1989-12-22 to current/open; source msha-controller-operator-history