# Relationship history for MSHA mine 0202603

Current hierarchy: **Gary T  Smith; Michael L  Smith → Superior Marble Llc → SUPERIOR MARBLE 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Mineral Development Inc → SUPERIOR MARBLE MILL; 1993-10-01 to 1997-06-19; source msha-controller-operator-history
- **controller_controls_mine:** Laurence U  Turley → SUPERIOR MARBLE MILL; 1993-10-01 to 1997-06-19; source msha-controller-operator-history
- **controller_controls_operator:** Laurence U  Turley → Mineral Development Inc; 1993-10-01 to 1997-06-19; source msha-controller-operator-history
- **operator_operates_mine:** Superior Marble Llc → SUPERIOR MARBLE MILL; 1997-06-20 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Michael L  Smith et al → SUPERIOR MARBLE MILL; 1997-06-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Michael L  Smith et al → Superior Marble Llc; 1997-06-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Gary T  Smith et al → Superior Marble Llc; 1997-06-20 to current/open; source msha-controller-operator-history