# Relationship history for MSHA mine 2901774

Current hierarchy: **Ted W  Elison → Southwest Mineral Corp Inc → Jones Camp 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:** Sierra Blanca Milling & Processing Corp → Jones Camp Pit; 1979-07-01 to 1980-07-22; source msha-controller-operator-history
- **controller_controls_mine:** Thomas Billy D → Jones Camp Pit; 1979-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Thomas Billy D → Sierra Blanca Milling & Processing Corp; 1979-07-01 to 1980-07-22; source msha-controller-operator-history
- **operator_operates_mine:** Southwest Mineral Corp Inc → Jones Camp Pit; 1980-07-23 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Ted W  Elison → Jones Camp Pit; 1980-07-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ted W  Elison → Southwest Mineral Corp Inc; 1980-07-23 to current/open; source msha-controller-operator-history