# Relationship history for MSHA mine 3800052

Current hierarchy: **Imerys S A → Kentucky-Tennessee Clay Company → K-T Clay 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** J M Huber Corp → K-T Clay Company; 1950-01-01 to 1995-06-05; source msha-controller-operator-history
- **controller_controls_mine:** J M Huber Corp → K-T Clay Company; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** J M Huber Corp → J M Huber Corp; 1950-01-01 to 1995-06-05; source msha-controller-operator-history
- **controller_controls_mine:** Hecla Mining Company → K-T Clay Company; 1986-06-17 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Kentucky-Tennessee Clay Company → K-T Clay Company; 1995-06-06 to 2001-03-27; source msha-controller-operator-history
- **controller_controls_operator:** Hecla Mining Company → Kentucky-Tennessee Clay Company; 1995-06-06 to 2001-03-27; source msha-controller-operator-history
- **operator_operates_mine:** Kentucky-Tennessee Clay Company → K-T Clay Company; 2001-03-28 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Imerys S A → K-T Clay Company; 2001-03-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Imerys S A → Kentucky-Tennessee Clay Company; 2001-03-28 to current/open; source msha-controller-operator-history