# Relationship history for MSHA mine 3101840

Current hierarchy: **Vulcan Materials Company → Vulcan Construction Materials, LLC → Spruce Pine**

- 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

- **controller_controls_mine:** Legacy Vulcan Corp (Form:Vulcan Materials Co) → Spruce Pine; 1950-01-01 to 2007-11-15; source msha-controller-operator-history
- **controller_controls_mine:** Claude  Greene → Spruce Pine; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Mayland Stone Company Inc → Spruce Pine; 1978-12-01 to 1999-03-01; source msha-controller-operator-history
- **controller_controls_operator:** Claude  Greene → Mayland Stone Company Inc; 1978-12-01 to 1999-03-01; source msha-controller-operator-history
- **operator_operates_mine:** Vulcan Construction Materials, LLC → Spruce Pine; 1999-03-02 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Legacy Vulcan Corp (Form:Vulcan Materials Co) → Vulcan Construction Materials, LLC; 1999-03-02 to 2007-11-15; source msha-controller-operator-history
- **controller_controls_mine:** Vulcan Materials Company → Spruce Pine; 2007-11-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Vulcan Materials Company → Vulcan Construction Materials, LLC; 2007-11-16 to current/open; source msha-controller-operator-history