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 whiterite), natural borates, natural magnesium sulphates (kieserite)

Mining of earth colors, fluorspar and other minerals valued chiefly as a source of chemicals

Guano mining

This class excludes :

Extraction of salt, see 0893;

Roasting of iron and pyrites, see 2011;

Manufacture of synthetic fertilizers and nitrogen compounds, see 2012.