About Black Salt Kala namak is a rock salt that has a strong, sulphurous smell. It is also known as Himalayan black salt, Sulemani namak, bit lobon, kala noon, or pada loon and manufactured from the salts mined in the regions surrounding the Himalayas. The condiment is composed largely of sodium chloride with several other components lending the salt its colour and smell. The smell is mainly due to its sulfur content. Because of the presence of Greigite in the mineral, it forms brownish pink to dark violet translucent crystals when whole. When ground into a powder, its color ranges from purple to pink. Production he raw material for producing kala namak was originally obtained from natural halite from mines in India, Nepal, Pakistan and Bangladesh in certain locations of the Himalayas salt ranges,[3][4] or from salt harvested from the North Indian salt lakes of Sambhar Salt Lake or Didwana and the Mustang District of Nepal.[5] Traditionally, the salt was transformed from its relatively colourless raw natural forms into the dark coloured commercially sold kala namak through a reductive chemical process that transforms some of the naturally occurring sodium sulfate of the raw salt into pungent hydrogen sulfide and sodium sulfide.[6] This involves firing the raw salts in a kiln or furnace for 24 hours while sealed in a ceramic jar with charcoal along with small quantities of harad seeds, amla, bahera, babul bark, or natron.[5][6] The fired salt melts, the chemical reaction occurs, and the salt is then cooled, stored, and aged prior to sale.[7][3] Kala namak is prepared in this manner in northern India with production concentrated in Hisar district, Haryana.[6] The salt crystals appear black and are usually ground to a fine powder that is pink.