# Relationship history for MSHA mine 4103555

Current hierarchy: **Caylor Doris → Caylor Specialty Materials Inc → CSM SAND**

- 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:** W & W Sand Company → CSM SAND; 1989-01-01 to 1989-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Weisse Terry → CSM SAND; 1989-01-01 to 1989-12-31; source msha-controller-operator-history
- **controller_controls_operator:** Weisse Terry → W & W Sand Company; 1989-01-01 to 1989-12-31; source msha-controller-operator-history
- **operator_operates_mine:** Caylor Specialty Materials Inc → CSM SAND; 1990-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Caylor Doris → CSM SAND; 1990-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Caylor Doris → Caylor Specialty Materials Inc; 1990-01-01 to current/open; source msha-controller-operator-history