Salt is one of the most popular ingredients used in Indian dishes. It has many varieties; one of them is sendha namak or rock salt. It is popularly known among those who kept fasting during the auspicious days of Navratri. This is the only type of 'salt' consumed during these nine days. It is the purest form of salt - unprocessed and raw. In fact, you can buy rock salt online, if you are worried about the quality and taste.