Class 1                Elements (metal and intermetallic alloys

                          carbides, metalloids and  non metals)

Class 2                Sulfides and sulphosalts 

Class 3                Halides

Class 4                Oxides, Hydroxides

Class 5                Carbonates, Nitrates

Class 6                Borates

Class 7                Sulfates, Chromates, Molibdates, Wolframates

Class 8                Phosphates, Arseniates, Vanadates

Class 9_1             Silicates - Neso - Soro - Cyclo silicates

Class 9_2             Silicates - Inosilicates

Class 9_3             Silicates - Phyllosilicates

Class 9_4             Silicates - Tectosilicates, Quartz, Chalcedony

Class A                Organic compound

Class M                     Meteorites