# Relationship history for MSHA mine 1700826

Current hierarchy: **Alton B  McQuade; Graden G  Tidd → STEELSTONE INDUSTRIES INC. → PIONEER CRUSHER #1**

- 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:** Alton B  McQuade et al → PIONEER CRUSHER #1; 2006-05-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Steelstone Industries Inc. → PIONEER CRUSHER #1; 2007-10-31 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Alton B  McQuade et al → Steelstone Industries Inc.; 2007-10-31 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Graden G  Tidd et al → Steelstone Industries Inc.; 2007-10-31 to current/open; source msha-controller-operator-history