Chapter 31
(Section VI:- Products of the Chemicals or allied industries)

Notes:

1. This Chapter does not cover:
(a) Animal blood of Chapter 5;
(b) Separate chemically defined compounds [other than those answering to the descriptions in Note 2(A), 3(A), 4(A) or 5 below];
(c) Cultured potassium chloride crystals (other than optical elements) weighing not less than 2.5 g. each, of heading No. 38.24; optical elements of potassium chloride (heading No. 90.01).

2. Heading No. 31.02 applies only to the following goods:
(A) Goods, which answer to one or other of the descriptions given below:
(i) Sodium nitrate, whether or not pure;
(ii) Ammonium nitrate, whether or not pure;
(iii) Double salts, whether or not pure, of ammonium sulphate and ammonium nitrate;
(iv) Ammonium sulphate, whether or not pure;
(v) Double salts (whether or not pure) or mixtures of calcium nitrate and ammonium nitrate;
(vi) Double salts (whether or not pure) or mixtures of calcium nitrate and magnesium nitrate;
(vii) Calcium Cyanamid, whether or not pure or treated with oil;
(viii) Urea, whether or not pure.
(B) Fertilizers consisting of any of the goods described in (A) above mixed together.
(C) Fertilizers consisting of ammonium chloride or of any of the goods described in (A) or (B) above mixed with chalk, gypsum or other inorganic non-fertilising substances.
(D) Liquid fertilizers consisting of the goods of sub-paragraph (A) (ii) or (viii) above, or of mixtures of those goods, in an aqueous or ammoniacal solution.

3. Heading No. 31.03 applies only to the following goods:
(A) Goods which answer to one or other of the descriptions given below:
(i) Basic slag;
(ii) Natural phosphates of Chapter 25, calcined or further heat-treated than for the removal of impurities;
(iii) Super phosphates (single, double or triple);
(iv) Calcium hydrogen orthophosphate containing not less than 0.2 per cent by weight of fluorine calculated on the dry anhydrous product.
(B) Fertilizers consisting of any of the goods described in (A) above, mixed together, but with no account being taken of the fluorine content limit.
(C) Fertilizers consisting of any of the goods described in (A) or (B) above, but with no account being taken of the flourine content limit, mixed with chalk, gypsum or other inorganic non-fertilising substances.

4. Heading No. 31.,04 applies only to the following goods:
(A) Goods which answer to one or other of the description given below:
(i) Crude natural potassium salts (for example, carnallite, kainite and sylvite);
(ii) Potassium chloride, whether or not pure, except as provided in Note 1(c) above;
(iii) Potassium sulphate, whether or not pure;
(iv) Magnesium potassium sulphate, whether or not pure.
(B) Fertilisers consisting of any of the goods described in (A) above mixed together.

5. Ammonium dihydrogenorthophosphate (mono-ammonium phosphate) and diammonium hydreogenorthophosphate (diammonium phosphate) whether or not pure, and inter-mixtures thereof, are to be classified heading No. 31.05.

6. For the purposes of heading No. 31.05, the term "other fertilisers" aplies only to products of a kind used as fertilisers and containing, as an essential constituent at least one of the fertilising elements nitrogen, phosphorus or potassium.