# Relationship history for MSHA mine 4000194

Current hierarchy: **Lhoist Group → Martin Marietta → Henry County Mines & Mill**

- 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:** H C Spinks Clay Company Inc → Henry County Mines & Mill; 1950-01-01 to 2003-02-23; source msha-controller-operator-history
- **controller_controls_mine:** Harry S  Carothers Sr → Henry County Mines & Mill; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Harry S  Carothers Sr → H C Spinks Clay Company Inc; 1950-01-01 to 2003-02-23; source msha-controller-operator-history
- **controller_controls_mine:** Franklin Industries Inc → Henry County Mines & Mill; 1950-01-01 to 2006-11-30; source msha-controller-operator-history
- **operator_operates_mine:** Spinks Clay Co. → Henry County Mines & Mill; 2003-02-24 to 2009-12-17; source msha-controller-operator-history
- **controller_controls_operator:** Franklin Industries Inc → Spinks Clay Co.; 2003-02-24 to 2006-11-30; source msha-controller-operator-history
- **controller_controls_mine:** Lhoist Group → Henry County Mines & Mill; 2006-12-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Lhoist Group → Spinks Clay Co.; 2006-12-01 to 2009-12-17; source msha-controller-operator-history
- **operator_operates_mine:** H.C. Spinks Clay Co. → Henry County Mines & Mill; 2009-12-18 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Lhoist Group → Henry County Mines & Mill; 2009-12-18 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Lhoist Group → H.C. Spinks Clay Co.; 2009-12-18 to current/open; source msha-controller-operator-history