# Relationship history for MSHA mine 4800597

Current hierarchy: **Minerals Technologies Inc → American Colloid Company Minerals Group → Upton West Mill**

- 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:** Amcol International Corp → Upton West Mill; 1950-01-01 to 2014-07-30; source msha-controller-operator-history
- **operator_operates_mine:** Federal Bentonite Div/Aurora Metal Company → Upton West Mill; 1950-01-01 to 1984-09-30; source msha-controller-operator-history
- **controller_controls_mine:** Panhandle Eastern Corp → Upton West Mill; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Panhandle Eastern Corp → Federal Bentonite Div/Aurora Metal Company; 1950-01-01 to 1984-09-30; source msha-controller-operator-history
- **controller_controls_mine:** Halliburton Company → Upton West Mill; 1984-06-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Federal Ore & Chemicals Inc → Upton West Mill; 1984-10-01 to 1987-03-15; source msha-controller-operator-history
- **controller_controls_operator:** Halliburton Company → Federal Ore & Chemicals Inc; 1984-10-01 to 1987-03-15; source msha-controller-operator-history
- **operator_operates_mine:** Federal Ore & Chemicals Inc → Upton West Mill; 1987-03-16 to 1987-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Dresser Industries Inc et al → Upton West Mill; 1987-03-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Dresser Industries Inc et al → Federal Ore & Chemicals Inc; 1987-03-16 to 1987-12-31; source msha-controller-operator-history
- **controller_controls_operator:** Halliburton Co et al → Federal Ore & Chemicals Inc; 1987-03-16 to 1987-12-31; source msha-controller-operator-history
- **operator_operates_mine:** American Colloid Company Minerals Group → Upton West Mill; 1988-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Amcol International Corp → American Colloid Company Minerals Group; 1988-01-01 to 2014-07-30; source msha-controller-operator-history
- **controller_controls_mine:** Minerals Technologies Inc → Upton West Mill; 2014-07-31 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Minerals Technologies Inc → American Colloid Company Minerals Group; 2014-07-31 to current/open; source msha-controller-operator-history