# Relationship history for MSHA mine 1401501

Current hierarchy: **Lenora R  Stone; James N  Stone Jr → Stone Sand Co.,Inc. → DARTMOUTH**

- 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:** Dartmouth Sand & Gravel → DARTMOUTH; 1986-08-01 to 2011-07-14; source msha-controller-operator-history
- **controller_controls_mine:** Robert L  Deines → DARTMOUTH; 1986-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Robert L  Deines → Dartmouth Sand & Gravel; 1986-08-01 to 2011-07-14; source msha-controller-operator-history
- **controller_controls_mine:** James N  Stone Jr et al → DARTMOUTH; 2005-09-12 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Stone Sand Co.,Inc. → DARTMOUTH; 2011-07-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** James N  Stone Jr et al → Stone Sand Co.,Inc.; 2011-07-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Lenora R  Stone et al → Stone Sand Co.,Inc.; 2011-07-15 to current/open; source msha-controller-operator-history