# Relationship history for MSHA mine 0301945

Current hierarchy: **Matt  Duffield; Luke B Duffield; David D Duffield → Ronnie Duffield Gravel Company → Austin 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

- **controller_controls_mine:** Ronald  Duffield → Austin Quarry; 1950-01-01 to 2020-06-07; source msha-controller-operator-history
- **operator_operates_mine:** Hamilton Aggregates, Inc. → Austin Quarry; 2007-03-01 to 2021-01-03; source msha-controller-operator-history
- **controller_controls_mine:** J Edward  Hamilton → Austin Quarry; 2007-03-01 to 2015-09-30; source msha-controller-operator-history
- **controller_controls_operator:** J Edward  Hamilton → Hamilton Aggregates, Inc.; 2007-03-01 to 2015-09-30; source msha-controller-operator-history
- **controller_controls_mine:** Michael E  Miller et al → Austin Quarry; 2015-10-01 to 2019-09-22; source msha-controller-operator-history
- **controller_controls_operator:** Michael E  Miller et al → Hamilton Aggregates, Inc.; 2015-10-01 to 2019-09-22; source msha-controller-operator-history
- **controller_controls_operator:** J Edward  Hamilton et al → Hamilton Aggregates, Inc.; 2015-10-01 to 2019-09-22; source msha-controller-operator-history
- **controller_controls_mine:** Michael E  Miller → Austin Quarry; 2019-09-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Michael E  Miller → Hamilton Aggregates, Inc.; 2019-09-23 to 2021-01-03; source msha-controller-operator-history
- **controller_controls_mine:** David D Duffield et al → Austin Quarry; 2020-06-08 to 2022-06-02; source msha-controller-operator-history
- **operator_operates_mine:** Ronnie Duffield Gravel Company → Austin Quarry; 2021-01-04 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** David D Duffield et al → Ronnie Duffield Gravel Company; 2021-01-04 to 2022-06-02; source msha-controller-operator-history
- **controller_controls_operator:** Ronald M Duffield et al → Ronnie Duffield Gravel Company; 2021-01-04 to 2022-06-02; source msha-controller-operator-history
- **controller_controls_operator:** Luke B Duffield et al → Ronnie Duffield Gravel Company; 2021-01-04 to 2022-06-02; source msha-controller-operator-history
- **controller_controls_operator:** Ronald  Duffield → Ronnie Duffield Gravel Company; 2021-01-04 to 2020-06-07; source msha-controller-operator-history
- **controller_controls_mine:** Luke B Duffield et al → Austin Quarry; 2022-06-03 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Luke B Duffield et al → Ronnie Duffield Gravel Company; 2022-06-03 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Matt  Duffield et al → Ronnie Duffield Gravel Company; 2022-06-03 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** David D Duffield et al → Ronnie Duffield Gravel Company; 2022-06-03 to current/open; source msha-controller-operator-history