# Relationship history for MSHA mine 3600051

Current hierarchy: **New Enterprise Stone & Lime Company Inc → New Enterprise Stone & Lime Co., Inc. → Egypt 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:** Essroc Cement → Egypt Quarry; 1950-01-01 to 2011-10-13; source msha-controller-operator-history
- **controller_controls_mine:** Italcementi Spa → Egypt Quarry; 1950-01-01 to 2016-10-11; source msha-controller-operator-history
- **controller_controls_operator:** Italcementi Spa → Essroc Cement; 1950-01-01 to 2011-10-13; source msha-controller-operator-history
- **controller_controls_mine:** New Enterprise Stone & Lime Company Inc → Egypt Quarry; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** New Enterprise Stone & Lime Co., Inc. → Egypt Quarry; 2011-10-14 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** New Enterprise Stone & Lime Company Inc → New Enterprise Stone & Lime Co., Inc.; 2011-10-14 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Heidelberg Materials AG → Egypt Quarry; 2016-10-12 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Heidelberg Materials AG → Essroc Cement; 2016-10-12 to 2011-10-13; source msha-controller-operator-history