# Relationship history for MSHA mine 4201973

Current hierarchy: **Keven B  Kester; Terry L  Kester → Santaquin Calcite Co. L.C. → Kester Mine & 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:** Santaquin Calcite Company → Kester Mine & Mill; 1986-04-01 to 2006-08-06; source msha-controller-operator-history
- **controller_controls_mine:** Clement A  Kester → Kester Mine & Mill; 1986-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Clement A  Kester → Santaquin Calcite Company; 1986-04-01 to 2006-08-06; source msha-controller-operator-history
- **operator_operates_mine:** Santaquin Calcite Co. L.C. → Kester Mine & Mill; 2006-08-07 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Terry L  Kester et al → Kester Mine & Mill; 2006-08-07 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Terry L  Kester et al → Santaquin Calcite Co. L.C.; 2006-08-07 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Keven B  Kester et al → Santaquin Calcite Co. L.C.; 2006-08-07 to current/open; source msha-controller-operator-history