Geologists call it Halite, chemists call it sodium chloride (NaCl)— the rest of us call it salt. Salt has a remarkable history, which dates back to the earliest civilizations. It is a vital component in the functioning of our bodies and it boasts over 14,000 known uses. Where does it all come from?
You would be hard-pressed to find a household without a salt shaker today, but this wasn’t always the case. Salt was a very rare commodity until the industrial revolution provided the technology to discover vast salt reserves. Salt was once used as a currency as valuable as gold – traded and fought over around the world.
“For millennia, salt represented wealth. Caribbean salt merchants stockpiled it in the basements of their homes. The Chinese, the Romans, the French, the Venetians, the Habsburgs, and numerous other governments taxed it to raise money for wars.”
Salt: A World History
Salt is used in thousands of ways all around the world. It is a jack of all trades that can enhance the flavor of foods in your kitchen and assist in the manufacture of paper, plastics, and fertilizers. Its preservative and antimicrobial effects are significant in the food processing industry, and it has an important role in the feeding of animals and plants.
The U.S. and China dominate in world salt production, accounting for 40% of the 250 million tons of salt produced each year. Kansas, Louisiana, Michigan, New York, Ohio, Texas, and Utah produced about 95% of the salt in the United States in 2016. In fact, the city of Detroit sits on one of the largest salt deposits in the world, and most of the salt used for de-icing our roadways is mined from an ancient seabed near Cleveland, 2,000 feet below Lake Erie.
It’s not just in your salt shaker! Salt is used across many industries. Source: U.S Geological Survey, 2017
All salt comes from the sea
Whether salt is mined from ancient sea beds under the city of Detroit, the Appalachian Mountains or the Himalayan Mountains; extracted from salt domes along the Louisiana coastline, or solar evaporated from the Atlantic or Pacific oceans – all salt comes from the sea!
There are three basic technologies to produce salt:
Deep-Shaft Mining is much like mining for any other mineral. Salt exists as deposits in underground ancient sea beds, which are typically miles long and thousands of feet deep. The majority of “rock salt” (used to de-ice highways and walkways) is produced this way. Have a look at the video!
Solution Mining is where wells, similar to oil and gas wells, are set up over salt deposits and fresh water is injected to dissolve the salt. The brine is then pumped out and taken to a plant for evaporation.
Solar Evaporation is the oldest method of salt production and is dependent on warmer climates. Salt is first captured in shallow ponds, where the wind and sun evaporate the water. The salt is then harvested either by hand or by machine.
Watch this video on how salt is harvested in California:
The Bottom Line:
No matter the type, all salt comes from our oceans! What differentiates salts are their source and the method of harvest.