# Relationship history for MSHA mine 0900900

Current hierarchy: **Henry Thomas  Mercer; Bobby E  Mercer → Gold Eagle Quarry → Gold Eagle Quarry**

- 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:** Walter Allen  Mc Cannon → Gold Eagle Quarry; 1950-01-01 to 2022-12-31; source msha-controller-operator-history
- **operator_operates_mine:** Crystal Blue Quarries Inc → Gold Eagle Quarry; 1979-01-01 to 1980-10-16; source msha-controller-operator-history
- **controller_controls_operator:** Walter Allen  Mc Cannon → Crystal Blue Quarries Inc; 1979-01-01 to 1980-10-16; source msha-controller-operator-history
- **operator_operates_mine:** Gold Eagle Quarry → Gold Eagle Quarry; 1980-10-17 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Henry Thomas  Mercer  et al → Gold Eagle Quarry; 1980-10-17 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Henry Thomas  Mercer  et al → Gold Eagle Quarry; 1980-10-17 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bobby E  Mercer  et al → Gold Eagle Quarry; 1980-10-17 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Edwin C  Williams → Gold Eagle Quarry; 2023-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Edwin C  Williams → Crystal Blue Quarries Inc; 2023-01-01 to 1980-10-16; source msha-controller-operator-history