# Relationship history for MSHA mine 4102822

Current hierarchy: **NG Operations LLC → Gold Bond Building Products, LLC → HARPER QUARRY**

- 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:** Lafarge S A → HARPER QUARRY; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Avalon Industries Inc → HARPER QUARRY; 1979-01-01 to 1981-10-19; source msha-controller-operator-history
- **controller_controls_mine:** Hugo C  Werner → HARPER QUARRY; 1979-01-01 to 1981-10-19; source msha-controller-operator-history
- **controller_controls_operator:** Hugo C  Werner → Avalon Industries Inc; 1979-01-01 to 1981-10-19; source msha-controller-operator-history
- **operator_operates_mine:** Gold Bond Building Products → HARPER QUARRY; 1981-10-20 to 1993-06-30; source msha-controller-operator-history
- **controller_controls_operator:** Lafarge S A → Gold Bond Building Products; 1981-10-20 to 1993-06-30; source msha-controller-operator-history
- **operator_operates_mine:** National Gypsum Company → HARPER QUARRY; 1993-07-01 to 1995-09-20; source msha-controller-operator-history
- **controller_controls_mine:** National Gypsum Company → HARPER QUARRY; 1993-07-01 to 1995-09-20; source msha-controller-operator-history
- **controller_controls_operator:** National Gypsum Company → National Gypsum Company; 1993-07-01 to 1995-09-20; source msha-controller-operator-history
- **operator_operates_mine:** New NGC, Inc. → HARPER QUARRY; 1995-09-21 to 2004-03-31; source msha-controller-operator-history
- **controller_controls_mine:** Spangler Companies Inc → HARPER QUARRY; 1995-09-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Spangler Companies Inc → New NGC, Inc.; 1995-09-21 to 2004-03-31; source msha-controller-operator-history
- **operator_operates_mine:** National Gypsum of Texas, LP → HARPER QUARRY; 2004-04-01 to 2007-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Spangler Companies Inc → HARPER QUARRY; 2004-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Spangler Companies Inc → National Gypsum of Texas, LP; 2004-04-01 to 2007-12-31; source msha-controller-operator-history
- **operator_operates_mine:** New NGC Incorporated → HARPER QUARRY; 2008-01-01 to 2021-10-11; source msha-controller-operator-history
- **controller_controls_operator:** Spangler Companies Inc → New NGC Incorporated; 2008-01-01 to 2021-10-11; source msha-controller-operator-history
- **controller_controls_mine:** NG Operations LLC → HARPER QUARRY; 2021-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Gold Bond Building Products, LLC → HARPER QUARRY; 2021-10-12 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** NG Operations LLC → Gold Bond Building Products, LLC; 2021-10-12 to current/open; source msha-controller-operator-history