# Relationship history for MSHA mine 3607172

Current hierarchy: **Graymont Ltd → Graymont (Pa) Inc → GENTZEL 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **controller_controls_mine:** Warner Company → GENTZEL QUARRY; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Warner Company → GENTZEL QUARRY; 1981-07-01 to 1986-01-22; source msha-controller-operator-history
- **controller_controls_operator:** Warner Company → Warner Company; 1981-07-01 to 1986-01-22; source msha-controller-operator-history
- **operator_operates_mine:** Bellefonte Lime Company Inc → GENTZEL QUARRY; 1986-01-23 to 1998-06-07; source msha-controller-operator-history
- **controller_controls_mine:** Philip J  Senechal → GENTZEL QUARRY; 1986-01-23 to 1998-06-07; source msha-controller-operator-history
- **controller_controls_operator:** Philip J  Senechal → Bellefonte Lime Company Inc; 1986-01-23 to 1998-06-07; source msha-controller-operator-history
- **operator_operates_mine:** Graymont (Pa) Inc → GENTZEL QUARRY; 1998-06-08 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Graymont Ltd → GENTZEL QUARRY; 1998-06-08 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Graymont Ltd → Graymont (Pa) Inc; 1998-06-08 to current/open; source msha-controller-operator-history