Where Does Salt Naturally Come From? The Origins of Our Most Common Condiment

December 20, 2025 •

4 min read

An estimated 280 million tonnes of salt are produced worldwide annually, but few people truly understand its natural origins. This article explores the geological and natural processes that answer the question: where does salt naturally come from?

Quick Summary

Salt originates from both modern oceans via solar evaporation and from ancient, dried-up seas now trapped in underground deposits. It is extracted through mining, solution mining to create brine, and the natural process of evaporation.

Key Points

Ancient Sea Beds: Much of the world's salt is mined from underground deposits created millions of years ago when ancient oceans evaporated and were subsequently buried by geological activity.
Solar Evaporation: A natural and age-old method of harvesting salt involves collecting seawater in large, shallow ponds and allowing the sun and wind to evaporate the water, leaving behind salt crystals.
Solution Mining: This modern technique extracts salt from underground deposits by injecting freshwater to dissolve the salt, creating a brine that is then evaporated at the surface.
Saline Lakes: Landlocked bodies of water like the Great Salt Lake accumulate salt from surrounding rocks carried in by streams. With no outlet, evaporation concentrates the minerals into salt deposits.
Trace Minerals: The color and taste of some salts, like pink Himalayan salt, come from trace minerals incorporated into the sodium chloride crystals during their formation.

From Ancient Oceans to Underground Mines: The Formation of Rock Salt

Millions of years ago, vast inland seas and saline lakes underwent intense periods of evaporation in hot, dry climates. As the water disappeared, it left behind thick layers of salt crystals, primarily the mineral halite (sodium chloride). Over eons, these salt deposits were buried under layers of sediment, rock, and soil, creating the immense subterranean salt beds we see today. These ancient geological formations are now a major source of the world's salt supply, accessed through a process known as rock salt mining.

Modern Rock Salt Extraction: Mining and Solution Mining

There are two primary methods for extracting salt from these buried deposits: dry mining and solution mining. Dry mining often employs the "room and pillar" technique, where explosives or specialized machines cut into the salt beds, leaving large support pillars intact. This process breaks the rock salt into chunks that are then crushed and transported to the surface. A modern alternative, continuous mining, uses boring machines to grind the salt into smaller pieces as they advance.

Solution mining, on the other hand, involves a different approach, particularly useful for deposits that are harder to access with conventional mining. Freshwater is pumped deep underground to dissolve the salt, creating a concentrated brine solution. This brine is then pumped back to the surface, where it is purified and evaporated to produce high-purity salt crystals.

The World's Biggest Salt Factory: Solar Evaporation

Seawater contains a staggering amount of dissolved salt, roughly 3.5% by weight, making the world's oceans another primary natural source. The most ancient and natural method for harvesting this salt is through solar evaporation, a process used for millennia in coastal regions with arid climates.

Here is a step-by-step list of how sea salt is harvested through solar evaporation:

Collection: Seawater is channeled into a series of shallow, interconnected ponds known as salt pans or salterns.
Concentration: In the initial ponds, sunlight and wind cause the water to evaporate, raising the salinity level. Less soluble minerals, like calcium carbonate, precipitate out during this stage.
Crystallization: The highly concentrated brine is then moved to crystallization ponds. Once saturated, sodium chloride begins to crystallize and settle on the pond floor.
Harvesting: When a thick enough layer of salt has formed, it is harvested, often using mechanical scrapers or rakes. The harvested salt is then washed and dried before packaging.

Natural Salt Lakes and Flats

Besides oceans and ancient sea deposits, significant salt accumulations occur in landlocked saline lakes and salt flats. These are found in closed basins with no natural outlet for the water. Over thousands of years, dissolved salts from surrounding rocks are carried into the lake by rainwater and streams. As the water evaporates, the salt concentration builds up, eventually leading to crystallization. The Bonneville Salt Flats in Utah and the Great Salt Lake are prime examples of this phenomenon.

Comparison of Salt Production Methods


Feature	Solar Evaporation (Sea Salt)	Rock Salt Mining (Dry)	Solution Mining (Brine)
Source	Oceans, saline lakes	Ancient sea beds	Ancient sea beds
Energy Source	Sun, wind (renewable)	Explosives, machinery, fuel	Water, fuel for evaporation
Purity	Varies; contains trace minerals	Varies; requires purification	High; can be very pure after refining
Extraction	Raking, mechanical scraping	Drilling, blasting, crushing	Pumping and evaporation
Byproducts	Magnesium, potassium salts	Impurities in rock	Residues from purification
Environment	Best in dry, warm climates	Anywhere deep deposits exist	Anywhere deep deposits exist

What Makes Pink and Black Salt Different?

While most salt is pure sodium chloride, the presence of other minerals can give it distinct colors and flavors. For instance, Himalayan pink salt, mined from ancient sea beds in Pakistan, gets its characteristic hue from trace minerals like iron oxide. Hawaiian red salt (Alaea salt) is infused with volcanic red clay, giving it a brick-red color and unique flavor profile. Himalayan black salt, or kala manak, is actually purplish-red and contains sulfur compounds that give it a distinctive sulfuric smell and flavor.

Conclusion: The Ubiquitous Mineral from Diverse Origins

In conclusion, the answer to where does salt naturally come from is multifaceted. From the slow, sun-powered evaporation of modern oceans to the brute-force mining of ancient, buried seabeds, and the subtle chemistry of saline lakes, salt is a ubiquitous mineral with diverse natural origins. The journey of salt, whether from a sea pan in the Mediterranean or a mine deep beneath the Himalayas, illustrates the incredible geological history of our planet and the ingenuity humans have applied to harvest this essential resource. For additional information on the types of salt and their origins, resources such as the Salt Association offer a deeper dive into the industry's practices and history [https://saltassociation.co.uk/].

Frequently Asked Questions

Sea salt is harvested from the evaporation of modern seawater and retains trace minerals from its marine origin. Rock salt, or halite, is mined from ancient sea beds and may contain impurities or be refined to a high purity.

Pink Himalayan salt is rock salt mined from ancient deposits and gets its color from trace minerals, particularly iron oxide. Standard table salt is often more heavily processed, with added iodine and anti-caking agents, and has a finer grain.

While the initial salinity of the oceans was influenced by volcanic activity releasing salt ions, today's salt doesn't come directly from volcanoes. Salt deposits can be found near volcanic areas due to ancient geological processes, not recent volcanic eruptions.

No, salt is found in oceans, but also in vast underground deposits (rock salt), saline lakes, and salt flats. Much of the ocean's salt originated from rocks on land that were eroded and carried into the sea.

The oldest method of salt production is solar evaporation, which involves collecting seawater in ponds and letting the sun and wind naturally evaporate the water to leave behind salt crystals.

Solution mining is a modern technique where water is injected into deep underground salt beds to dissolve the salt, creating a brine that is then pumped to the surface for purification and evaporation.

Salt accumulates in inland lakes when water flows in from rivers and streams, carrying dissolved minerals from surrounding rocks. Because these lakes have no outlet, the water evaporates, but the salt remains, concentrating over time.