1. Adbri Ltd.
2. Austin White Lime Company
3. Boral Limited
4. Carmeuse
5. Celtic Sustainables
6. Cheney Lime & Cement Company
7. Cornish Lime Company
8. GP Group
9. Graymont Limited
10. LAFARGE by Holcim Group
11. Lhoist Group
12. Linwood Mining & Minerals Corp.
13. Minerals Technologies Inc.
14. Mississippi Lime Company
15. Neelkanth Group
16. Nordkalk Corporation
17. Ognyanovo K AD
18. Omya AG
19. Pete Lien & Sons Inc.
20. SCR-Sibelco NV
21. Shandong Zhongxin Calcium Industry Co. Ltd.
22. Sigma Minerals Ltd.
23. Tarmac Trading Limited by CRH Company
24. United States Lime & Minerals Inc.
25. Wagners Holding Company Ltd.