# Relationship history for MSHA mine 0203003

Current hierarchy: **Dale  Turner → Tombstone Materials, Inc. → Emerald 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:** L. Sheldon & Co. Corp. → Emerald Mine; 2002-10-22 to 2005-02-27; source msha-controller-operator-history
- **controller_controls_mine:** Loren J  Sheldon → Emerald Mine; 2002-10-22 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Loren J  Sheldon → L. Sheldon & Co. Corp.; 2002-10-22 to 2005-02-27; source msha-controller-operator-history
- **operator_operates_mine:** Tombstone Sand & Rock LLC → Emerald Mine; 2005-02-28 to 2007-08-05; source msha-controller-operator-history
- **controller_controls_mine:** Dale  Turner → Emerald Mine; 2005-02-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Dale  Turner → Tombstone Sand & Rock LLC; 2005-02-28 to 2007-08-05; source msha-controller-operator-history
- **operator_operates_mine:** Tombstone Materials, Inc. → Emerald Mine; 2007-08-06 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Dale  Turner → Emerald Mine; 2007-08-06 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Dale  Turner → Tombstone Materials, Inc.; 2007-08-06 to current/open; source msha-controller-operator-history