| Standard International Trade Classification (SITC) - level 2 - Division | 66 | Non-metallic mineral manufactures, n.e.s. | 
                
                  
                    | Standard International Trade Classification (SITC) - level 4 - Sub-group | 6631 | Millstones and grindstones, grinding wheels and other | 
                
                  
                    | Standard International Trade Classification (SITC) - level 4 - Sub-group | 6632 | Natural or artificial abrasive powder or grain | 
                
                  
                    | Standard International Trade Classification (SITC) - level 4 - Sub-group | 6633 | Manufactures of mineral materials,n.e.s.(excl.ceramic) | 
                
                  
                    | Standard International Trade Classification (SITC) - level 4 - Sub-group | 6635 | Slag and rock wool, exfoliated vermiculite and other | 
                
                  
                    | Standard International Trade Classification (SITC) - level 4 - Sub-group | 6637 | Refractory ceramic goods | 
                
                  
                    | Standard International Trade Classification (SITC) - level 4 - Sub-group | 6638 | Manufactures of asbestos; friction materials | 
                
                  
                    | Standard International Trade Classification (SITC) - level 4 - Sub-group | 6639 | Articles of ceramic materials, n.e.s. |