what is rock salt and why it is brown in colour. explain in detail
Answers
Rock salt is the mineral form of sodium chloride. Beds of rock salt were formed when seas of bygone ages dried up. They are brown in colour due to presence of impurities.
Halite more commonly known as Rock salt is a mineral formed from sodium chloride. It's chemical formula is NaCl and this also includes other variations of salt such as common salt and table salt. Rock salt tends to be the industrial name used for Halite.
It forms as isometric crystals and is typically colourless or white, but may also be other colours depending on the amount and type of impurities contained within it. The salt occurs in beds of sedimentary evaporite minerals. This is caused by large lakes and seas drying up. These salt beds can be hundreds of metres deep.
Halite crystals form very quickly in some rapidly evaporating lakes. England was covered by inland seas over 200 million years ago which helped create the layers of salt that are mined today. When very hot temperatures in the area evaporated the waters very slowly, they left large salt deposits under the earth. In the UK as the water evaporated and the salt crystals started to form they got their brownish colour from sand blown in from eastern deserts. However other geological influences mean the rock salt's colour can sometimes go from clear, to pink, to dark brown.
Rock salt is brown in colour due to the impurities present in it.