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Roger Weller, geology instructor

by Chung-ting Tsai
Physical Geology
Fall 2013

Importance of Salt

What is Salt?

Salt or NaCl is a rock that is mined underground. You can also find plenty of salt in the oceans. In fact, sea water contains the most salt. Sodium salt (NaCl) is a substance that occurs as cubic crystals in a transparent form. Salt crystals look like small cubes because the ions of sodium and chloride have bonded together. Salt forms all over the world as halite and evaporated salt water. Temperature affects the size and shape of crystals. Salt is clear to white in color, melts at 800 degrees Celsius, is 2.5 on Moh’s scale, is isometric and cubic, and has an atomic weight of 22.989768 (“What is Salt?”).



History of Salt

The earliest humans got their salt from natural salt concentration called salt licks. The people who live near the ocean chewed algae to get enough salt in their body. Salt became more important in the process of preserving milk, and meat from sheep, goats, horses, camels, reindeer, and cattle. Even today, some people such as the Inuit of the far north, the Middle East desert Bedouins, and the East African Masai people do not use other forms of salt. Two thousand years ago, Chinese people began to use the wells rich in salt water, and some of which are more than 0.6 miles (1.0 kilometers) deep underground. (“Time Magazine”).



How Is Salt Produced

As agriculture was developed, farming lead to population growth. Since the composition of the diet was mostly plant, it became necessary to find ways to get a greater amount of salt. So, there are different ways that salt is produced. In the salt production method, the sun first vaporizes the water. This method is particularly suitable for hot and arid areas near the ocean or near salty lakes, and in these areas, is still in use. Another method is the solar evaporation which develops into underground salt deposits that can be mined (“Salts From Around World”).


Benefits of Salt

1. Pharyngitis patients should gargle with salt water for anti-inflammatory and analgesic effects.

2. Patients with trachoma and conjunctivitis should wash with salt water every morning for eyesight treatment.

3. Salt can be added to tomato roots to treat frostbite.

4. For bee stings, scorpion stings, and centipede bites, if you wash the affected area immediately with brine, it can relieve pain, swelling, and detoxification.

5. If you wash your head with brine, the salt can reduce hair loss.

6. If you use fried salt and put it in a gauze wrap, that will heat the joints and help with rheumatism caused by arthritis.

7. In sports, the use of thermohaline can help avoid blisters on the feet and legs, as well as help with aching feet and fatigue in the next days.

8. Put a little salt in the bath water so the body can stop itching.

9. Gargling daily with salt water can eliminate bad breath.

10. Before singing, drink salt water to avoid losing your voice.

11. Early in the morning, drink a glass of salt water to help urinate. In the summer, drink salt water both to quench thirst and supplement the body’s salt.

12. While washing clothes that fade easily, add some salt to prevent fading.

13. When using a charcoal barbecue, sprinkle some salt to help with cleaning.

14. If one were to use salt when watering flowers, they will not wither as easy.

 15. Salt can erase black spots on bronze.


How is Salt Used

People have been using salt for cooking, cleaning, and de-icing. Although salt as a food supplement is most common, less than 5% of the salt in the United States is used for that purpose. Salt is used in the chemical industry for 70%, mainly as a source of chlorine. Salt is also used in a myriad of other uses such as removing snow from ice roads, softening water, preserving food, and stabilizing soil construction.


Types of Salt

Table salt – mined using water to create brine. Table salt, the one found in most salt shakers, is mined from salt deposits and has most of the minerals removed.  Most salt in the United States is sold with iodine added making it iodized salt. This salt is harvested by forcing water into a mine to create brine (salt/water mix). The brine is then evaporated leaving cubes of salt. 

The salt is refined from there to create varieties like:
Pickling salt, Canning salt, Coarse salt, Gos sel - fine grained without iodine or anti-caking preservatives. This is similar to table salt, but lacks the iodine and anti-caking additives that turn pickles dark and the pickling liquid cloudy. Pickles made with table salt would still be good to eat, but they wouldn't look as appetizing. 
Pretzel salt - large grained and does not melt quickly.

Rock salt - large crystal salt with a gray color due to minerals not removed from normal table salt. This form of salt is available in most grocery stores and also in hardware stores.

Popcorn salt - very fine grained salt that is a flakier version of table salt.

Iodized salt - contains a small amount of potassium iodide and dextrose as a dietary supplement to prevent thyroid disease.

Seasoned salt - table salt with herbs added like onion, hickory smoke or garlic.

Kosher salt, Koshering salt - also made from brine but this brine is continually raked during the evaporation process.

Kosher salt- is an additive-free coarse-grained salt. This salt was developed for the preparation of kosher meats in accordance with Jewish dietary laws. The salt itself is not kosher, but this is where the name comes from. The difference between table and kosher salt is that during the evaporation process, it is raked to give it a block-like structure which allows the salt to draw the blood out of meats. The raking makes kosher salt coarser and flakier than table salt, so it disperses more easily. This makes it lighter and less dense than table salt. It is also recommended to use kosher salt for cocktail glasses for drinks like margaritas. Since it is a lighter salt, there is less after taste with it.

Sea Salt - made from ocean or sea water and contains trace minerals not in the mined salts.


     Sea Salt is just that – salt gained from evaporating salt water collected from an ocean or sea.  The process is more costly then the mining process.  Sea salt is   typically less refined than other salts. Depending on the seawater used, you also get a variety of minerals in the sea salt. Due to this, there are numerous types of sea salts. 

     Black Salt, Kala Namak, and Sanchal - Significant for its strong sulfur odor (India), this salt is a pearly pink gray.  It is used in Indian cooking (“Nixon, Lindway S.”).


Grey salt, Celtic salt, Sel Gris – This salt is harvested from the light film of salt which forms during the evaporation process.  The gray or light purple color comes from the clay in the region of France where it is harvested, and it is collected using traditional Celtic hand methods.

Hawaiian sea salt – This salt has a distinctive pink hue from the Alaea added to it. The Alaea is volcanic red clay with a high content of iron oxide. This salt is used in many traditional Hawaiian dishes like Kahlua Pig and Hawaiian Jerky.

Coarse salt, Gos Sel, Gale Grosso - Is a larger grain salt which resists moisture and is intended to be ground. The uses of this salt include flavoring for soups and salt crusts on meats.

Flake salt - Shaped like snowflakes, the brine is made using the sun and wind for evaporation. Then the brine is slowly heated to create the flakes. 


Fleur de Sel, Flower of Salt, Flor De Sal - Skimmed from the top of salt ponds early in the process of evaporation, this is considered a great condiment salt; it is also good on grilled meats, in salads and on vegetables. The flavor, like wines, varies depending on the region it is harvested from. Typically it is from France, though some is produced in Portugal.

French sea salt - salt processing is lower than in the United States. This usually includes natural iodine. Coarse salt is good in salad, vegetables, and meats.

Smoked sea salt - another derivative, smoked sea salt is a salt. This is salt smoked over wood so a scent is added to the crystals. This salt makes soups, salads, pasta, and barbecue foods such as salmon taste delicious.


Fascinating Facts of Salt

            According to history of salt on Morton’s website, “The early Greeks worshipped salt no less than the sun, and had a saying that ‘no one should trust a man without first eating a peck of salt with him’ (the moral being that by the time one had shared a peck of salt with another person, they would no longer be strangers)” (“Salt History”).   



Works Cited


“A Brief History of Salt.” Time Magazine. Time, 1982. Web. 4 Nov. 2013.,9171,925341-1,00.html

Alden, Lori. “Salt.” The Cook’s Thesaurus. 1996-2005. Web.

Nixon, Lindway S. “Types of Black Salt.” Happy Herbivore Blog. N.p., 2012. Web. 4 Nov. 2013.

“Salts From Around World.” How Products Are Made. Advameg, n.d. Web. 4 Nov. 2013.

 “Salt History.” Morton Salt. Web.

Sodium Chloride ( NaCl ) Common Salt - Occurrence, Production, Properties and Applications “Sodium Chloride ( NaCl ) Common Salt - Occurrence, Production, Properties and Applications.” The A to Z of Materials and AZojomo, 2013. Web. 4 Nov. 2013.