# Relationship history for MSHA mine 1600352

Current hierarchy: **Atalco LLC → Atalco Gramercy LLC → Gramercy Operation**

- 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:** Kaiser Aluminum & Chemical Corp → Gramercy Operation; 1950-01-01 to 1989-09-30; source msha-controller-operator-history
- **controller_controls_mine:** Kaiser Aluminum & Chemical Corp → Gramercy Operation; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Kaiser Aluminum & Chemical Corp → Kaiser Aluminum & Chemical Corp; 1950-01-01 to 1989-09-30; source msha-controller-operator-history
- **operator_operates_mine:** Kaiser Aluminum & Chemical Corporation → Gramercy Operation; 1989-10-01 to 2004-09-30; source msha-controller-operator-history
- **controller_controls_mine:** Maxxam Inc → Gramercy Operation; 1989-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Maxxam Inc → Kaiser Aluminum & Chemical Corporation; 1989-10-01 to 2004-09-30; source msha-controller-operator-history
- **operator_operates_mine:** Noranda Alumina LLC → Gramercy Operation; 2004-10-01 to 2016-10-27; source msha-controller-operator-history
- **controller_controls_mine:** Noranda Aluminum Company → Gramercy Operation; 2004-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Noranda Aluminum Company → Noranda Alumina LLC; 2004-10-01 to 2016-10-27; source msha-controller-operator-history
- **operator_operates_mine:** Atalco Gramercy LLC → Gramercy Operation; 2016-10-28 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** DADA Holdings LLC → Gramercy Operation; 2016-10-28 to 2021-06-30; source msha-controller-operator-history
- **controller_controls_operator:** DADA Holdings LLC → Atalco Gramercy LLC; 2016-10-28 to 2021-06-30; source msha-controller-operator-history
- **controller_controls_mine:** Concord Resources Ltd et al → Gramercy Operation; 2021-07-01 to 2026-09-20; source msha-controller-operator-history
- **controller_controls_operator:** Concord Resources Ltd et al → Atalco Gramercy LLC; 2021-07-01 to 2026-09-20; source msha-controller-operator-history
- **controller_controls_operator:** DADA Holdings LLC et al → Atalco Gramercy LLC; 2021-07-01 to 2026-09-20; source msha-controller-operator-history
- **controller_controls_mine:** Atalco LLC → Gramercy Operation; 2026-09-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Atalco LLC → Atalco Gramercy LLC; 2026-09-21 to current/open; source msha-controller-operator-history