# Relationship history for MSHA mine 1500064

Current hierarchy: **Cemex S A → Rinker Materials South Central, Inc. → Park City 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

- **operator_operates_mine:** State Contracting & Materials Division → Park City Quarry; 1950-01-01 to 1978-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Medusa Corp → Park City Quarry; 1950-01-01 to 1979-01-31; source msha-controller-operator-history
- **controller_controls_operator:** Medusa Corp → State Contracting & Materials Division; 1950-01-01 to 1978-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Medusa Corp → Park City Quarry; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Crane Company → Park City Quarry; 1978-12-13 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Medusa Aggregates Company → Park City Quarry; 1979-01-01 to 1988-10-06; source msha-controller-operator-history
- **controller_controls_operator:** Crane Company → Medusa Aggregates Company; 1979-01-01 to 1988-10-06; source msha-controller-operator-history
- **operator_operates_mine:** Medusa Aggregates Company → Park City Quarry; 1988-10-07 to 2002-03-31; source msha-controller-operator-history
- **controller_controls_operator:** Medusa Corp → Medusa Aggregates Company; 1988-10-07 to 2002-03-31; source msha-controller-operator-history
- **controller_controls_mine:** CSR Ltd → Park City Quarry; 2000-07-01 to 2003-03-31; source msha-controller-operator-history
- **operator_operates_mine:** Rinker Materials South Central, Inc. → Park City Quarry; 2002-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** CSR Ltd → Rinker Materials South Central, Inc.; 2002-04-01 to 2003-03-31; source msha-controller-operator-history
- **controller_controls_mine:** Rinker Group Ltd → Park City Quarry; 2003-04-01 to 2007-07-09; source msha-controller-operator-history
- **controller_controls_operator:** Rinker Group Ltd → Rinker Materials South Central, Inc.; 2003-04-01 to 2007-07-09; source msha-controller-operator-history
- **controller_controls_mine:** Cemex S A → Park City Quarry; 2007-07-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Cemex S A → Rinker Materials South Central, Inc.; 2007-07-10 to current/open; source msha-controller-operator-history