# Relationship history for MSHA mine 3302633

Current hierarchy: **Heidelberg Materials AG → Heidelberg Materials Midwest Agg, Inc. → PIKETON SAND & GRAVEL**

- 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:** Standard Slag Company → PIKETON SAND & GRAVEL; 1950-01-01 to 1989-09-30; source msha-controller-operator-history
- **controller_controls_mine:** Standard Slag Company → PIKETON SAND & GRAVEL; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Standard Slag Company → Standard Slag Company; 1950-01-01 to 1989-09-30; source msha-controller-operator-history
- **controller_controls_mine:** Hanson PLC → PIKETON SAND & GRAVEL; 1988-11-14 to 2007-08-22; source msha-controller-operator-history
- **operator_operates_mine:** Standard Lafarge → PIKETON SAND & GRAVEL; 1989-10-01 to 1994-01-02; source msha-controller-operator-history
- **controller_controls_mine:** Lafarge S A → PIKETON SAND & GRAVEL; 1989-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Lafarge S A → Standard Lafarge; 1989-10-01 to 1994-01-02; source msha-controller-operator-history
- **operator_operates_mine:** Piketon Sand & Gravel-Div/Davon Inc → PIKETON SAND & GRAVEL; 1994-01-03 to 2001-03-30; source msha-controller-operator-history
- **controller_controls_mine:** Davon Inc → PIKETON SAND & GRAVEL; 1994-01-03 to 2001-03-30; source msha-controller-operator-history
- **controller_controls_operator:** Davon Inc → Piketon Sand & Gravel-Div/Davon Inc; 1994-01-03 to 2001-03-30; source msha-controller-operator-history
- **operator_operates_mine:** Hanson Aggregates Davon, LLC → PIKETON SAND & GRAVEL; 2001-03-31 to 2023-03-15; source msha-controller-operator-history
- **controller_controls_mine:** Hanson PLC → PIKETON SAND & GRAVEL; 2001-03-31 to 2007-08-22; source msha-controller-operator-history
- **controller_controls_operator:** Hanson PLC → Hanson Aggregates Davon, LLC; 2001-03-31 to 2007-08-22; source msha-controller-operator-history
- **controller_controls_mine:** Heidelberg Materials AG → PIKETON SAND & GRAVEL; 2007-08-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Heidelberg Materials AG → Hanson Aggregates Davon, LLC; 2007-08-23 to 2023-03-15; source msha-controller-operator-history
- **operator_operates_mine:** Heidelberg Materials Midwest Agg, Inc. → PIKETON SAND & GRAVEL; 2023-03-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Heidelberg Materials AG → Heidelberg Materials Midwest Agg, Inc.; 2023-03-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hanson PLC → Heidelberg Materials Midwest Agg, Inc.; 2023-03-16 to 2007-08-22; source msha-controller-operator-history