| HADDOUK, Jennifer Aurelie Mathilde ACTIVE | Secretary | 30 Jun 2026 | | | | C/O Weir Minerals Europe Limited, Halifax Road, Todmorden, OL14 5RT, England |
| JONES, Franklin Randolph ACTIVE | Director | 21 May 2021 | | United States | November 1973 | C/O Weir Minerals Europe Limited, Halifax Road, Todmorden, OL14 5RT, England |
| STITZEL, Adam Dale ACTIVE | Director | 20 Feb 2026 | | Belgium | October 1976 | C/O Weir Minerals Europe Limited, Halifax Road, Todmorden, OL14 5RT, England |
| OWENS, Jon Vernon RESIGNED | Secretary | 05 Jun 1997 | 22 Dec 1998 | | | Le Grand Closin 10, 1380 Ohain, Belguim, 1380, Belguim |
| PIGNOL, Alphonse RESIGNED | Secretary | | 05 Jun 1997 | | | 10 Les Sabines, Ecully 69130, France |
| ROBINSON, Stephen Beresford RESIGNED | Secretary | 22 Dec 1998 | 30 Jun 2026 | | | Rue Des Fours A Chaux, Zoning Industriel, 7080 Frameries, Belguim, Belgium |
| THOMAS, Kevin Scott RESIGNED | Secretary | 05 Oct 2012 | 11 Jul 2018 | | | 2141, Nw 25th Avenue, Portland, Oregon 97210, United States |
| WEISSHAAR, Meredith RESIGNED | Secretary | 11 Jul 2018 | 31 Jan 2019 | | | 2141, Nw 25th Avenue, Portland, 97210, United States |
| ABEL, Todd William RESIGNED | Director | 22 Feb 2017 | 29 Dec 2023 | United States | May 1964 | Esco (Uk) Limited, Ings Road, Doncaster, DN5 9SN, United Kingdom |
| BARIL, Francois Romeo RESIGNED | Director | 01 Jul 2003 | 30 Sep 2005 | | August 1965 | 63 Rue Victor Hugo, 1410 Waterloo, Belgium |
| COLLINS, Calvin William RESIGNED | Director | 01 Jan 2011 | 01 Jan 2012 | Usa | October 1958 | 2141 Nw 25th Avenue, Portland, Or 97210, United States |
| FITZGERALD, Sean Stanley RESIGNED | Director | 04 Apr 2023 | 30 Jun 2026 | United States | January 1969 | Esco (Uk) Limited, Ings Road, Doncaster, DN5 9SN, United Kingdom |
| FONNER, Pat RESIGNED | Director | 10 Nov 1999 | 17 Sep 2012 | Usa | July 1949 | 19725, Nw Phillips Road, Hillsboro, Oregon, 97-124-8135, Usa |
| HUEY, Gene RESIGNED | Director | | 01 Jan 2012 | Usa | June 1948 | 9218, Nw Finzer Court, Portland, Oregon 97229, Usa |
| HUGET, Larry R RESIGNED | Director | 22 Dec 1998 | 31 Dec 2010 | Usa | March 1945 | 31000 S W Riverlane Road, West Linn, Oregon 97068, Usa |
| KASKARIAN, Philippe RESIGNED | Director | 01 Jan 2018 | 31 Mar 2026 | France | February 1963 | Esco (Uk) Limited, Ings Road, Doncaster, DN5 9SN, United Kingdom |
| KERSHAW, Jeffrey Walter RESIGNED | Director | 17 Sep 2012 | 21 Oct 2015 | United States Of America | June 1966 | 2141, Nw 25th Avenue, Portland, Oregon 97210, Usa |
| KERSHAW, Jeffrey Walter RESIGNED | Director | 01 Oct 2005 | 20 Apr 2009 | | June 1966 | Van Dijcklaan 49, 3080 Tervuren, Belgium |
| LIAN, Aaron Benjamin RESIGNED | Director | 20 Apr 2009 | 01 Apr 2013 | Belgium | December 1969 | 12, Avenue Des Chasseurs, Waterloo, 1410, Belgium |
| NEILSON, Andrew James RESIGNED | Director | 15 Jul 2020 | 04 Apr 2023 | United States | November 1975 | Esco (Uk) Limited, Ings Road, Doncaster, DN5 9SN, United Kingdom |
| O'NEILL, John RESIGNED | Director | 10 Nov 1999 | 01 Jul 2003 | | April 1962 | Chemin Je La Fraite 7, 1380 Omain, Belgium |
| OWENS, Jon RESIGNED | Director | 01 Jan 2012 | 15 Jul 2020 | United States | May 1962 | 2141, Nw 25th Avenue, Portland, Oregon 97210, United States |
| OWENS, Jon Vernon RESIGNED | Director | 05 Jun 1997 | 10 Nov 1999 | | May 1962 | Le Grand Closin 10, 1380 Ohain, Belguim, 1380, Belguim |
| PIGNOL, Alphonse RESIGNED | Director | | 05 Jun 1997 | | December 1939 | 10 Les Sabines, Ecully 69130, France |
| PRATT, Steven RESIGNED | Director | | 22 Dec 1998 | | November 1946 | 1060 Cherry Circle Lake, Oswego, Oregon 97034, Usa |
| SIMONUTTI, Ermanno RESIGNED | Director | 01 Apr 2013 | 31 Dec 2017 | Belgium | May 1970 | Esco (Uk) Limited, Ings Road, Doncaster, DN5 9SN, United Kingdom |
| SONGER, James RESIGNED | Director | 27 Mar 1992 | 10 Nov 1999 | | September 1946 | 12 245 N W Kearney, Portland, Oregon, FOREIGN, Usa |
| VERLINICH, Ray RESIGNED | Director | 01 Jan 2012 | 15 Feb 2017 | United States Of America | September 1955 | 2141, Nw 25th Avenue, Portland, Oregon 97210, Usa |
| ESCO CORPORATION RESIGNED | Director | | 22 Dec 1998 | | | 2141 Nw 25th Avenue, Portland, Oregon, FOREIGN, Usa |