# Relationship history for MSHA mine 1519297

Current hierarchy: **John T  Quintrell → Smoky Quartz → UZ No. 2**

- 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:** United  Company → UZ No. 2; 2004-11-15 to 2009-04-29; source msha-controller-operator-history
- **operator_operates_mine:** Sapphire Coal Company → UZ No. 2; 2008-08-27 to 2021-08-05; source msha-controller-operator-history
- **controller_controls_operator:** United  Company → Sapphire Coal Company; 2008-08-27 to 2009-04-29; source msha-controller-operator-history
- **controller_controls_mine:** Metinvest B V → UZ No. 2; 2009-04-30 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Metinvest B V → Sapphire Coal Company; 2009-04-30 to 2021-08-05; source msha-controller-operator-history
- **controller_controls_mine:** John T  Quintrell → UZ No. 2; 2021-07-30 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Smoky Quartz → UZ No. 2; 2021-08-06 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** John T  Quintrell → Smoky Quartz; 2021-08-06 to current/open; source msha-controller-operator-history