… with a manganese content of 20 % or more, calculated on the dry weight. …
Explanatory notes
… with a manganese content of 20 % or more, calculated on the dry weight. The principal ores generally covered by this heading are : (a) Braunite, manganese oxide. (b) … on the dry weight (the ores and concentrates being heated to a temperature of 105 to 110 °C); those with a …