Salt Mining

Halite rock salt

Salt (NaCl) is a mineral made up of white cube-shaped crystals composed of two elements, sodium and chlorine. It is translucent, colourless, and odourless. For centuries salt has had a permanent place in the life of human beings. Salt was considered sacred, a gift from the Gods; it was used to confirm oaths and sacrifices. Salt served as money at various times and places, and the quest for salt has been the cause of bitter warfare. Offering bread and salt to visitors is, in many cultures, a traditional sign of hospitality.

Prior to industrialization, it was expensive, dangerous, and labor intensive to harvest the mass quantities of salt necessary for food preservation and seasoning. Mining salt caused rapid dehydration. Other problems related to accidental excessive sodium intake. This made salt an extremely valuable commodity throughout history. Entire economies were based solely on salt production and trade.

Inca ancient salt production farm in Peru.

The World's oldest salt mine. The “Man in Salt” greets visitors on their journey through time at the Salzwelten Hallstatt Mine, Austria. In 1734 a corpse preserved in salt was discovered in the deposit.

The Dachstein-Hallstättersee region has been appointed a UNESCO World Cultural and Natural Heritage Site.

At the Chehrabad Salt Mine, Iranian miners recently uncovered the sixth "salt man" to be found in the last fifteen years. Salt men are ancient corpses killed or crushed in the cave and mummified by the extreme conditions. Hair, flesh and bone are all preserved by the dry salinity of the cave, and even internal organs have been found intact. The first salt man, dated to 300 A.D., was discovered in 1993, sporting a long white beard, iron knives and a single gold earring. In 2004 another mummy was discovered 50 feet away, followed by another in 2005 and a "teenage" boy later that year. The oldest of the salt men found is truly ancient and has been carbon dated to 9550 B.C.

Egyptians may have been the first civilization to preserve fish and meat with salt. Food that could be preserved was highly valuable. Recognizing the worth of preserving food, Egyptians turned to trade. The Egyptians did not export salt by itself, it was bulky and difficult to transport, but rather food that was salted, which transported easily without spoiling and had a value added per pound. Ancient Egypt's trade started a 4000 year-long history of trade and export involving salt and food.

Ancient method of boiling brine into pure salt in China.

In the Iron Age, the British evaporated salt by boiling seawater or brine from salt spri­ngs in small clay pots over open fires. Roman salt-making entailed boiling the seawater in large lead-lined pans. In ancient Rome, salt on the table was a mark of a very rich patron; those who sat nearer the host were "above the salt," and those less favored were "below the salt".

Malta Roman salt flats

Ancient Roman Glass Salt Dishes

Roman salt mining was often done by slave or prison labor, and life expectancy was low. The Roman historian Pliny the Elder stated as an aside in his Natural History's discussion of sea water, that "[I]n Rome ... the soldier's pay was originally salt and the word 'salary' derives from it ..."

Roman Salt Pans in Hortales.

A salt waterfall in the Nemocon salt mine, Colombia. The mine is a popular tourist attraction.

Salar de Uyuni, the world’s biggest salt desert, in southwestern Bolivia.

The Maras salt mines in Cuzco, Peru. The Maras mines have been a source of salt since ancient pre-Incan civilizations and comprise about 3,000 small pools constructed on the slope of a mountain at the Urubamba valley in the Andean region of Cuzco.

Pools of mineral-colored water gathered on salt flats in holes dug by salt collectors on the Senegalese coastline. Women collect salt by hand into 50kg (110lbs) sacks, which sell for about $2. The salt is mainly used for preserving fish in areas without electricity

A truck drives between ponds at Rio Tinto’s Dampier Salt Limited’s facility at Port Hedland, about 1,600 km (960 mi) north of Perth, Australia.

A laborer works at a salt production factory in Nangqian county, northwest China’s Qinghai province.

Workers collect blocks of salt from the salt pan of Ethiopia’s Danakil depression. Generations of Afar salt merchants have hauled blocks of salt along camel caravan routes from the depression to the Tigray highlands.

The Saint Kinga’s Chapel in the Wieliczka Salt Mine near Krakow, Poland. The historic mine extends for a total of about 300 km (186 miles) and functioned continuously since the Middle Ages until 1996, when it was finally depleted.