Alkali earth metals produce white coloured salts with halogens like chlorine. But Muriate of potassium available in India generally used as a fertilizer is pink coloured(reddish white actually), why is it so?

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    $\begingroup$ You found your nomenclature in XIX century book? Or older? $\endgroup$
    – Mithoron
    Sep 23, 2019 at 15:40
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    $\begingroup$ Yes muriatic acid is an old name of HCl. Muriatic means brine, but for strange reason muriatic earth is magnesium oxide :) $\endgroup$
    – AChem
    Sep 23, 2019 at 19:46
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    $\begingroup$ If it’s sold as a fertilizer, it probably won’t be pure KCl. In addition, it may be coloured pink on purpose so it isn’t mistaken for table salt. $\endgroup$
    – Jan
    Sep 24, 2019 at 2:35
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    $\begingroup$ The color is due to iron oxides as impurities. $\endgroup$ Sep 24, 2019 at 4:28
  • $\begingroup$ Related: How is Persian blue rock salt made? $\endgroup$
    – andselisk
    Sep 24, 2019 at 13:42

1 Answer 1


If you have seen pink salt crystals from Khewra mines in Pakistan (the so-called Himalayan pink salt) sold at exorbitant rates in grocery stores, you would find out it is nothing but NaCl with a small amount of iron oxides as stated above. If you dissolve large tablespoons of such salt crystals in water, you will see a brownish precipitate sitting at the bottom on the container.

The word muriate reminded me of ancient chemistry books of the 1940s. It is a very very old name for a salt of hydrochloric acid.


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