# Relationship history for MSHA mine 0900985

Current hierarchy: **Worley Robert W → Majestic Blue Quarry → Majestic Blue 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:** Gran-Stone Inc → Majestic Blue Quarry; 1986-06-01 to 1987-08-16; source msha-controller-operator-history
- **controller_controls_mine:** Darlene H  Dye  et al → Majestic Blue Quarry; 1986-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Darlene H  Dye  et al → Gran-Stone Inc; 1986-06-01 to 1987-08-16; source msha-controller-operator-history
- **operator_operates_mine:** Majestic Blue Quarry → Majestic Blue Quarry; 1987-08-17 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Worley Robert W → Majestic Blue Quarry; 1987-08-17 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Worley Robert W → Majestic Blue Quarry; 1987-08-17 to current/open; source msha-controller-operator-history