Special Salts and Guano

The Chinese scraped a white tangy salt off rocks called huo yao, the fire drug, which we know in the west as “the salt of the stone,” saltpeter. In a mixture of charcoal dust and sulphur, you have a remarkable eruption.

Scraping saltpeter off rocks was not exactly a reliable way to gather massive quantities of it. Extracting it from manure spread over land was also a slow and smelly process. For every pound of manure, a few crystals would grow.

In the mud areas of the River Ganges in India, the local population had been using saltpeter for a long time in their agricultural practices of fertilization with manure. The first documented reference to saltpeter is found in the early 17^th century when the English East India Company considered importing it from India in the early 1620s. The first recorded shipment to England was made in 1626. Saltpeter became one of the most important items traded by the English company.

On the three Chincha Islands located 21 km off the coast of Peru, on a group of rocks inhabited exclusively by flocks of birds, boobies, cormorants, and penguins, over thousands of years, bird droppings had formed a crust over a hundred feet deep, one of the finest natural fertilizers called guano.

The Inca called the bird droppings huanu, hence our term guano. Sprinkling it onto their fields as fertilizer, Incas valued guano just like gold and considered the killing of birds a capital crime.

Peru started trading the guano in 1840, after using Chinese labor to harvest the highly flammable fertilizer. By late 1850, the Chincha guano was exhausted when the workers struck rocks. Economists calculated that by 1860, 4,000 Chinese workers had died working in extremely noxious conditions. Peru’s source of riches was exhausted in two decades.

Peru had another unique salt called caliche found in the northern reaches they controlled in the Atacama Desert. The word caliche is derived from Quechua and it means salt.

Caliche appeared as a crust found by a stroke of luck by locals traveling from the Andes foothills to the Pacific Ocean. While making camp for the night and building fires, they noticed rocks on the ground sparking and igniting.

The explosive and fertile caliche is made up of sodium chloride (table salt), nitrates, iodates, sulphates, and chlorides. The caliche is slightly different from saltpeter in that it has sodium nitrate rather than potassium nitrate.

Nobody is quite sure how the caliche appeared in the northern parts of the Atacama Desert. According to Ed Conway, there are theories:

1.      The product of an eerie fog that often forms across the desert at night and morning.

2.      These salts washed down from the Andes.

3.      Caliche was deposited here by an ancient sea.

Even though the deposits were mostly located in Peruvian and Bolivian territory, according to Conway, it was “enterprising Chilean immigrants who discovered most of the caliche, did most of the mining, and forged the all-important links with English and German financiers who provided the capital for their businesses." [mid 1870s]

The greedy decision by Bolivia to enact a retroactive tax of ten cents per quintal (100 lbs.) of nitrates exported from the area, even though they signed a treaty in 1874, pledging not to impose taxes on mineral exploitation, gave rise to a serious conflict. The railway’s manager, George Hicks, refused to pay and sought refuge on a Chilean warship stationed off the coast. Chilean troops occupied the area and the port a few days later.

Following the Ten Cents War which lasted five years (1879-1884), fought between Chile, Peru, and Bolivia over the nitrate-rich Atacama Desert region, Chile won “control over the most important mineral resources in the world - not just the nitrates of the Atacama, but the world’s biggest reserves of copper and lithium.” Bolivia lost its coastline and Chile became “a resource superpower.” (Ed Conway, Material World, p. 170)