# Relationship history for MSHA mine 4400068

Current hierarchy: **Titan Cement International S A → Roanoke Cement Co., LLC → ROANOKE CEMENT 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Lone Star Cement Inc → ROANOKE CEMENT COMPANY; 1950-01-01 to 1986-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Lone Star Industries Inc → ROANOKE CEMENT COMPANY; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Lone Star Industries Inc → Lone Star Cement Inc; 1950-01-01 to 1986-12-31; source msha-controller-operator-history
- **operator_operates_mine:** Tarmac-Lonestar Inc → ROANOKE CEMENT COMPANY; 1987-01-01 to 1988-12-18; source msha-controller-operator-history
- **controller_controls_mine:** Lone Star Industries Inc & Tarmac Plc → ROANOKE CEMENT COMPANY; 1987-01-01 to 1988-12-18; source msha-controller-operator-history
- **controller_controls_operator:** Lone Star Industries Inc & Tarmac Plc → Tarmac-Lonestar Inc; 1987-01-01 to 1988-12-18; source msha-controller-operator-history
- **operator_operates_mine:** Roanoke Cement Company → ROANOKE CEMENT COMPANY; 1988-12-19 to 1992-12-13; source msha-controller-operator-history
- **controller_controls_mine:** Tarmac Plc → ROANOKE CEMENT COMPANY; 1988-12-19 to 1992-12-13; source msha-controller-operator-history
- **controller_controls_operator:** Tarmac Plc → Roanoke Cement Company; 1988-12-19 to 1992-12-13; source msha-controller-operator-history
- **operator_operates_mine:** Roanoke Cement Co., LLC → ROANOKE CEMENT COMPANY; 1992-12-14 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Titan Cement Co S A - Tarmac Plc Et Al → ROANOKE CEMENT COMPANY; 1992-12-14 to 2002-03-07; source msha-controller-operator-history
- **controller_controls_operator:** Titan Cement Co S A - Tarmac Plc Et Al → Roanoke Cement Co., LLC; 1992-12-14 to 2002-03-07; source msha-controller-operator-history
- **controller_controls_mine:** Titan Cement International S A → ROANOKE CEMENT COMPANY; 2002-03-08 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Titan Cement International S A → Roanoke Cement Co., LLC; 2002-03-08 to current/open; source msha-controller-operator-history