Ok Namak Udyog Naubasta, Kanpur, Uttar Pradesh

Rock salt powder, is the mineral form of sodium chloride (NaCl). Halite forms isometric crystals. The mineral is typically colorless or white, but may also be light pink, red, orange . It commonly occurs with other evaporite deposit minerals such as several of the sulfates, halides, and borates.

Alums are useful for a range of industrial processes. They are soluble in water; have a sweetish taste; react acid to litmus; and crystallize in regular octahedra.

Black salt, is known as rock salt or kala namak, is specially find in central India. Their looks is finely ground, pinkish gray salt is rich in minerals. Its smoky, tangy taste heightens the flavor in foods.

The most common of this spice is to impart the special characteristics flavor to the tangy fresh salads called chaats.It is also regularly used in small quantities in chutneys,raitas,pickles and many other savory indian snacks,adding a very different flavor than just using regular salt.

Rock salt is the common name for halite. It is a rock, rather than a mineral, and this is what makes it different to the salt you might find on your table, although it does share many characteristics.