# Relationship history for MSHA mine 3301470

Current hierarchy: **Mc Cann Donald → Cd Materials Inc → Holland Pit**

- 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:** Blazer Materials Corp → Holland Pit; 1950-01-01 to 1983-04-03; source msha-controller-operator-history
- **controller_controls_mine:** Blazer J J Construction Company Inc → Holland Pit; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Blazer J J Construction Company Inc → Blazer Materials Corp; 1950-01-01 to 1983-04-03; source msha-controller-operator-history
- **operator_operates_mine:** Cd Materials Inc → Holland Pit; 1983-04-04 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Mc Cann Donald → Holland Pit; 1983-04-04 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mc Cann Donald → Cd Materials Inc; 1983-04-04 to current/open; source msha-controller-operator-history