Kala Namak or black salt is used extensively in Indian cuisine as a condiment or added to chaats, chutneys, all kind of fruits, raitas and many other savoury snacks.
Chaat masala, the famous Indian spice blend, gets its characteristic aroma from black salt. Adding kala namak to a dish gives it a very different flavour than if regular salt were used. In appearance, this mineral is brownish pink to dark violet in crystal form, and light pink when ground into powder.
In Ayurvedic medicine, Kala Namak is considered a cooling spice and is used as a laxative and digestive aid. It is also believed to relieve intestinal gas and heartburn besides helpful to cure goiter.