# Relationship history for MSHA mine 4300080

Current hierarchy: **Cyprus Amax Minerals Company → Cyprus Windsor Minerals Corp → Hammondsville 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

- **operator_operates_mine:** Windsor Minerals Inc → Hammondsville Mine; 1950-01-01 to 1989-06-04; source msha-controller-operator-history
- **controller_controls_mine:** Johnson & Johnson → Hammondsville Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Johnson & Johnson → Windsor Minerals Inc; 1950-01-01 to 1989-06-04; source msha-controller-operator-history
- **controller_controls_mine:** Cyprus Amax Minerals Company → Hammondsville Mine; 1988-05-13 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Cyprus Windsor Minerals Corp → Hammondsville Mine; 1989-06-05 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Cyprus Amax Minerals Company → Cyprus Windsor Minerals Corp; 1989-06-05 to current/open; source msha-controller-operator-history