# Relationship history for MSHA mine 0404482

Current hierarchy: **Centurion Gold Ltd & U S Precious Metals Inc → Siskon Gold Corp → Big Horn Mine**

- 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:** Trost Paul B & William F Martin → Big Horn Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Martin Trost Associates → Big Horn Mine; 1980-11-01 to 1984-08-21; source msha-controller-operator-history
- **controller_controls_operator:** Trost Paul B & William F Martin → Martin Trost Associates; 1980-11-01 to 1984-08-21; source msha-controller-operator-history
- **controller_controls_mine:** Terra Industries Inc → Big Horn Mine; 1981-06-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Inspiration Mines Inc → Big Horn Mine; 1984-08-22 to 1991-05-31; source msha-controller-operator-history
- **controller_controls_operator:** Terra Industries Inc → Inspiration Mines Inc; 1984-08-22 to 1991-05-31; source msha-controller-operator-history
- **operator_operates_mine:** Siskon Gold Corp → Big Horn Mine; 1991-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Centurion Gold Ltd & U S Precious Metals Inc → Big Horn Mine; 1991-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Centurion Gold Ltd & U S Precious Metals Inc → Siskon Gold Corp; 1991-06-01 to current/open; source msha-controller-operator-history