Black Rock Salt
Black salt (Hindi kala namak or sanchal) is an unrefined mineral salt that is actually pinkish gray and has a strong sulfuric flavor. Black salt is mined in India and is used extensively in Indian cuisine as a condiment or added to chaats, chutneys, raitas and many other savory Indian snacks. Chaat masala, an Indian spice blend, is dependent upon black salt for its characteristic aroma and flavor. Chemically, black salt is sodium chloride, with iron, sulfurous compounds and trace minerals.