Kala Namak salt, or black salt, is a variation of pink Himalayan salt, which has a surprising aroma of hard-boiled eggs. It is produced by hand in northern India by melting pink salt at high temperature, and adding in particular harad seeds rich in sulphur. The heated salt is then cooled in ceramic jars, stored and aged before being sold. Kala Namak black salt has an aroma that can be described as sulphurous. It is often likened to the smell of hard-boiled eggs. Like all salts, black salt is mainly composed of sodium chloride like table salt and other culinary salts. Black salt also contains hydrogen sulfide, which is responsible for the odor, and iron sulphide, which gives it its color. Its aroma combined with its salty taste is good for giving a salty note to dishes.