# Relationship history for MSHA mine 1100081

Current hierarchy: **St Charles Sand Company → Kimaterials → Kimaterials, Inc.**

- 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:** St Charles Sand Company → Kimaterials, Inc.; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Valstad Quarry, Inc. → Kimaterials, Inc.; 1950-01-01 to 2005-04-07; source msha-controller-operator-history
- **controller_controls_mine:** Harold M  Valstad → Kimaterials, Inc.; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Harold M  Valstad → Valstad Quarry, Inc.; 1950-01-01 to 2005-04-07; source msha-controller-operator-history
- **operator_operates_mine:** Kimaterials → Kimaterials, Inc.; 2005-04-08 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** St Charles Sand Company → Kimaterials; 2005-04-08 to current/open; source msha-controller-operator-history