Mining of chemical and fertilizer minerals

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

This class also includes:

• guano mining