# Relationship history for MSHA mine 0300062

Current hierarchy: **Vulcan Materials Company → Vulcan Construction Materials, LLC → Black Rock 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

- **controller_controls_mine:** Legacy Vulcan Corp (Form:Vulcan Materials Co) → Black Rock Quarry; 1950-01-01 to 2007-11-15; source msha-controller-operator-history
- **operator_operates_mine:** Black Rock Sand Gravel & Quarries → Black Rock Quarry; 1950-01-01 to 1993-09-30; source msha-controller-operator-history
- **controller_controls_mine:** W W  Smith → Black Rock Quarry; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** W W  Smith → Black Rock Sand Gravel & Quarries; 1950-01-01 to 1993-09-30; source msha-controller-operator-history
- **operator_operates_mine:** Black Rock Quarries Inc → Black Rock Quarry; 1993-10-01 to 1996-11-21; source msha-controller-operator-history
- **controller_controls_mine:** Mark  Clark → Black Rock Quarry; 1993-10-01 to 1996-11-21; source msha-controller-operator-history
- **controller_controls_operator:** Mark  Clark → Black Rock Quarries Inc; 1993-10-01 to 1996-11-21; source msha-controller-operator-history
- **operator_operates_mine:** Vulcan Construction Materials, LLC → Black Rock Quarry; 1996-11-22 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Legacy Vulcan Corp (Form:Vulcan Materials Co) → Vulcan Construction Materials, LLC; 1996-11-22 to 2007-11-15; source msha-controller-operator-history
- **controller_controls_mine:** Vulcan Materials Company → Black Rock Quarry; 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