Water softener salt is one of the most familiar uses of an ancient mineral. Indeed, every block, tablet and granule we sell at W.E. Softeners started life as halite, the natural crystalline form of sodium chloride. In fact, human civilisations have fought wars over this mineral for thousands of years.

Salt is mostly sodium chloride (NaCl). It comes from two main sources. First, sea water carries about 2.5% salinity along the UK coastline. Second, deep underground there are seams of rock salt left behind by prehistoric sea beds. These dried out millions of years ago. Both sources supply the water softener salt that keeps modern softeners running.

Where water softener salt comes from

Most UK water softener salt comes from the Cheshire salt fields. These deposits formed over 250 million years ago. Back then, the UK sat much closer to the equator and the climate was hot and dry. As the prehistoric sea evaporated, the salt crystals mixed with sand and marl. Consequently, that mineral mix gives Cheshire rock salt its pink colour.

Modern producers then purify the mined salt into blocks, tablets and granules. However, the journey from seabed to softener cabinet spans thousands of years of human history.

Rubbing salt in the wounds

The earliest evidence of salt processing dates back to around 6,000 BC. From that point on, salt quickly became one of the most valuable substances on earth. People used it to season food, preserve meat and clean wounds. Later, they used it for tanning leather, defrosting roads, fertilising crops and chemical production.

Less obvious uses of salt

Salt also has surprising uses. For instance, potters use it to glaze ceramics. In addition, drillers stabilise boreholes by adding salt to drilling fluid. The salt stops the wall of the hole from collapsing.

Religions and cultures across the world feature salt too. People cast spilt salt over their shoulder. Stories tell of people turning into pillars of salt. Some surround their homes with salt to ward off bad energy. Notably, in medieval Africa salt traded at the same value as gold.

Salt and healing

Medically, salt water cleans and promotes healing through osmosis. The sodium chloride solution draws liquid out of body cells on contact. If bacteria sit in that liquid, the salt draws them out too. As a result, the wound and surrounding skin end up cleaner.

Traders moved salt by boat across the Mediterranean. Camel caravans carried it across the Sahara. Routes known as salt roads stretched across Europe. The universal need for salt drove nations to declare war and impose taxes on its production, export and sale.

Salt of the Earth

Producers extract salt from brine in several ways. They use solar evaporation, traditional mining or twentieth century vacuum evaporation methods. Each approach takes time, effort and investment.

Worldwide salt production

Worldwide salt production reached approximately 300 million tonnes in 2018. The top six producers were China (68 million), the USA (42 million), India (29 million), Germany (13 million), Canada (13 million) and Australia (12 million).[1]

Production has grown sharply over the last 45 years. In 1975 it stood at 162 million tonnes. By contrast, 2019 saw 293 million tonnes worldwide. That is an increase of around 181%.[2]

The UK sits in the middle of the world producer table. We create around 6 million tonnes a year, just 2% of the world total.

Where does all that salt go? About 6% goes into food. Around 12% goes into water conditioning, including the water softener salt for domestic softeners. Another 8% de-ices roads and railways. Agriculture takes 6%. The rest, 68%, feeds manufacturing and other industrial processes.[3]

Salt and the rise of cities

Throughout history, the availability of salt shaped civilisations and communities. In England, the suffix “wich” in a place name means it once supplied salt. Sandwich and Norwich both come from this tradition.

Salt also fuelled the rise of some of the world’s greatest cities. Liverpool, for example, was just a small English port. Then it became the major exporting hub for salt from the Cheshire mines. As a result, it traded much of the world’s salt through the 19th century.

“Let there be work, bread, water and salt for all” – Nelson Mandela

How modern producers make salt

If you have ever travelled abroad you may have seen salinas like the one pictured below. Warmer countries use the sun to evaporate seawater into white salt by solar evaporation.

White salt forms when evaporation produces pure crystals of sodium chloride. As the crystals form, workers skim them from the brine and dry them in containers or mounds.

Our ancestors also used traditional methods. These include sleeching (also known regionally as muldefang) and pot processes that boil brine over a fire. Today, you mostly see these processes in historical re-enactment demonstrations.

Crystal size depends on the extraction method. Quicker evaporation makes finer crystals. As crystals form, producers top up the brine and skim them off. This stops bitter salts from sticking to the sodium chloride.

Without strong sun, UK processors used artificial heat to speed up evaporation. In the past, they burned half a tonne of coal to make one tonne of salt in a large open pan. As fuel costs rose, however, vacuum evaporation took over.

Vacuum evaporation began at the start of the 20th century. Producers inject steam into sealed chambers with reduced atmospheric pressure to heat the brine. Consequently, the process uses less energy and produces cubic or spherical crystals from purified brine.

Natural brine streams can be up to eight times stronger than sea water. Rock salt dissolves into the water until the solution can take no more. The stronger the salt solution, the less heat it needs to evaporate. Salt from unrefined brine in open pans tends to look spiky and clustered.

In Essex, the Maldon Crystal Salt Company still uses the open pan method. As a result, it produces larger flaked crystals that are hollow and pyramidal in shape.

Modern salt manufacturers stress the purity and cheapness of their product. Traditional sea salt producers, by contrast, emphasise the natural mineral content and the special crystal form.

Business is the salt of life

For centuries, smaller producers dotted the UK’s coast. As methods evolved, more producers moved inland. Eventually, the market reached a point where the industry needed regulation and price control.

The first salt taxes

In 1759, the British East India Company took control of land near Calcutta where salt works already operated. They doubled the land rent and imposed transit charges on the salt. These rules became the first Salt Tax.

From that point on, the British East India Company adjusted the tax repeatedly. Later, the British Government took over in 1857 and continued the practice to suit their strategic objectives.

In China, salt taxes go back even further, as far as 300BC. At one time, salt taxes made up over half of China’s revenue. Notably, they helped fund the building of the Great Wall.

Salt taxes in England

In England, the Domesday Book mentions historical salt taxes. However, these lapsed before patents were issued in Tudor times.

The Government tried to reinstate salt taxes in 1641 during the Commonwealth period. Huge protests followed. As a result, Parliament withdrew the taxes when the monarchy returned in 1660.

William III later reintroduced salt taxes in 1693. The duty stood at two shillings a bushel on foreign salt and one shilling on native salt. Fishery salt escaped the duty. In 1696 the tax doubled. It then stayed in place until 1825. At its peak, around 600 full-time officials collected these taxes.

In 1835, the Government appointed a salt commission to review the existing tax. The commission recommended taxing Indian salt to enable the sale of imported English salt.

The Salt Union

From the start, critics attacked the salt taxes. The Chamber of Commerce in Bristol became one of the first to petition against them.

Eventually, the English salt trade fell into turmoil. Large producers fulfilled contracts at 50% below cost price while smaller producers undercut each other. In response, the industry founded the Salt Union on 5th July 1888.

The Union pulled together 64 firms and monopolised the English salt trade for many years. It controlled prices, raised them often, bought out some salt works and closed down smaller operations to centralise production. Finally, in 1936, Imperial Chemical Industries (ICI) absorbed the Salt Union.

Salt rocks the Empire

Meanwhile, in India, Mahatma Gandhi launched a salt protest on 12th March 1930. He set out from Sabarmati Ashram with 79 followers. Together they walked 240 miles to Dandi on the Arabian Sea coast.

Film clips and images of Gandhi spread across the world. Consequently, the Dandi March, also known as the Salt March, became headline news. Gandhi reached Dandi on 6th April 1930.

After his morning devotions, Gandhi waded to the sea shore. He picked up a handful of salt and proclaimed the end of the British Empire. The police arrested him along with thousands of national leaders.

The salt tax in India remained in force until March 1947. Eventually, the Interim Government of India abolished it.

Today, the route from Sabarmati Ashram to Dandi forms the Dandi Path, a recognised historical heritage route. The National Salt Satyagraha Memorial and museum opened in Dandi on 30th January 2019. The monument stands 40 metres high. It takes the form of a steel frame symbolising two hands. Notably, it holds a 2.5-tonne glass cube that represents a salt crystal.

The water softener salt we sell today

As a Wiltshire family business serving the water softener industry for over 60 years, we have seen plenty of change in the salt side of things. Salt shortages, price changes, and a steady technology shift have all left their mark. In particular, water softener salt has moved from loose granular, to tablets, to the modern compact blocks used in non-electric softeners today. Each step has made it simpler for our customers to keep their softened water flowing.

We stock water softener salt for every make and model of softener at competitive prices. Collect from our Holt showroom, or arrange a delivery to your door if you live within our operational region.

Order water softener salt

Block, tablet, granular and curve salt are all in stock at the Holt showroom. Order online for click and collect, or call us to arrange a salt delivery.

Sources:

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

https://www.statista.com/statistics/237162/worldwide-salt-production

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

The Salt Industry by Andrew and Annelise Fielding, A Shire Book