Calcium Nitrate is sometimes available as a fertilizer and it is easy to make KNO3 from this if you have Potassium sulphate. If you mix a solution of the calcium nitrate and the potassium sulphate (in the proper proportions), calcium sulphate will immediately precipitate out as it is insoluble and you will be left with KNO3 in solution. You could also use KCl instead of K Sulphate, I will leave it to the reader to figure out the amounts/concentrations to use.
The following shows various ways to obtain Potassium Nitrate (KNO3) from the other, sometimes more available, chemicals.
KNO3 from Ammonium Nitrate and KCl
KNO3 from NaNO3 and other sources
Below is what you are liable to meet on a bag of KNO3
Info from Danish origin KNO3. Bag has markings in 6 different languakes: GB, F, I, D, NL and E. All markings indicate 13,5% Nitrogen and 46% watersoluble K2O, exept GB, that lists also the K -content. Heres the GB section word to word: ------------------------------------- NITRATE OF POTASH 13-0-46 Low in chlorine Total Nitrogen (N) 13,5% of which Nitric Nitrogen (N) 13,5% Potassium Oxide soluble in water (K2O)46,0% (38,2% K) NET weight 25 KG Marketed in the UK by: Kemira Horticulture, Ince Chester CH2 4LB -------------------------------------- Product name in other languakes: (GB, NITRATE OF POTASH) F, NITRATE DE POTASSIUM I, NITRATO DI POTASSIO D, KALIUMNITRAT NL, KALISALPETER E, NITRATO POTASICO Also in bag generally: POTASSIUM NITRATE (KNO3) 13-0-46 HORTICULTURAL GRADE CRYSTALLIZED -HIT THE BACK BUTTON ON YOUR BROWSER