| Class 891: Mining of chemical and fertiliser minerals |
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| This class includes:
- mining of natural phosphates and natural potassium salts - mining of native sulphur - extraction and preparation of pyrites and pyrrhotite, except roasting - mining of natural barium sulphate and carbonate (barytes and witherite), natural borates, natural magnesium sulphates (kieserite) - mining of earth colours, fluorspar and other minerals valued chiefly as a source of chemicals |