- Barite 4.2g/ml - Barite 4.1g/ml. Bentonite. Drilling grade - API Specification 13A Section 9 - API Specification 13A Section 19 (OCMA grade Bentonite) ... (Locally Manufactured in Oman) Bauxite Iron Ore Pelletization grade (Locally Manufactured in Oman) Fertilizer Industry. Bentonite Fertilizer grade (Locally Manufactured in Oman)