# Relationship history for MSHA mine 0504807

Current hierarchy: **United States Lime & Minerals Inc → Colorado Lime Company → Colorado Lime Company**

- 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:** United States Lime & Minerals Inc → Colorado Lime Company; 1999-06-04 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Alternative Mining Methods LLC → Colorado Lime Company; 2005-01-31 to 2005-08-31; source msha-controller-operator-history
- **controller_controls_mine:** Keith  Buhrdorf et al → Colorado Lime Company; 2005-01-31 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Keith  Buhrdorf et al → Alternative Mining Methods LLC; 2005-01-31 to 2005-08-31; source msha-controller-operator-history
- **controller_controls_operator:** David A  Schaaf  et al → Alternative Mining Methods LLC; 2005-01-31 to 2005-08-31; source msha-controller-operator-history
- **operator_operates_mine:** Colorado Lime Company → Colorado Lime Company; 2005-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** United States Lime & Minerals Inc → Colorado Lime Company; 2005-09-01 to current/open; source msha-controller-operator-history