https://www.soest.hawaii.edu/GG/ASK/rocksalt.html

You might know this substance as table salt. and... Actually, rock salt is not K2SO4; it is NaCl. It can have impurities of gypsum (CaSO4) and sylvite (KCl) but it is ...

http://jes.ecsdl.org/content/106/1/54.abstract

Abstract. Because of the known interference of certain impurities and the suspected effect of others in the electrolytic cell processes for the production of sodium ...

https://www.thoughtco.com/simple-method-to-purify-sodium-chloride-from-rock-salt-606076

Learn how to apply two simple purification techniques to get table salt by removing impurities from rock salt.

http://files.dep.state.pa.us/water/Wastewater%20Management/WastewaterPortalFiles/Rock%20Salt%20Paper%20final%20052711.pdf

The high content of sodium in the rock salt can result in interference issues for ... The chemical composition of rock salt, compared to SGEW, yielded very low ...

https://en.wikipedia.org/wiki/Halite

Halite commonly known as rock salt, is a type of salt, the mineral (natural) form of sodium chloride (NaCl). Halite forms isometric crystals. The mineral is typically colorless or white, but may also be light blue, dark blue, purple, pink, red, orange, yellow or gray depending on inclusion of other materials, impurities, ...

https://en.wikipedia.org/wiki/Salt

Salt is a mineral composed primarily of sodium chloride (NaCl), a chemical compound belonging to the larger class of salts; salt in its natural form as a crystalline mineral is known as rock salt or ..... during which a brine solution is treated with chemicals that precipitate most impurities (largely magnesium and calcium salts).

https://www.cargill.com/how-are-rock-salt-and-solar-salt-different

Because solar salt is made from a brine, we can rid solar salt of insoluble impurities. The purity of solar salt is always going to be higher than that of rock salt.

http://www.erocksalt.com/rock-salt-uses/

Dec 11, 2018 ... In its primitive appearance, rock salt looked like huge irregular crystals with different ... Rock salt's tonality is related to the impurities it has.

https://www.cargill.com/what-is-rock-salt

Because rock salt does not undergo any kind of chemical purification, it's going to retain all of the natural impurities that are present in the mineral itself.

https://www.rocksalt.co.uk/inspiration/what-is-rock-salt

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  ...