Region: Iran  The latest addition to our salt collection: Persian Blue Salt is considered the most rare salt in the world only found along the mountain ranges in Iran. It’s an ancient salt formed over 110 million years ago and has not been exposed to modern pollutants making it the cleanest and purest salt on the market.  Giving a unique visual appearance and slight mineral finish is magnesium, which naturally occurs in the salt and give some grains their characteristic blue hue.