Salt is essential to human survival. In Central Europe, the Celts were among the very the first salt miners, and grew wealthy from establishing an international salt trade. So, where did the early Irish get their salt?
There’s a fascinating chapter on Celtic salt miners and the European salt trade in general in Mark Kurlansky’s excellent book, Salt: A World History. He details how the Celts were innovators, who realized the importance of salt, and developed the means to mine it successfully in the Alps and other central European locations. They became very wealthy through the international salt trade, and their traders travelled all the way to the Middle East, North Africa, and China.
This made me curious about the salt trade in ancient Ireland. Where did their salt come from? Are there ancient mine workings? And, what about modern salt works? After all, salt is one of the essential ingredients for human survival, and they must have got the necessary amount of salt from somewhere. So, I did a little research to find out more.
According to Kurlansky, hunter-gatherer societies get all the salt they need from wild game, and the necessity to add salt to a diet only comes when people settle down and begin agriculture. So, the early inhabitants of Ireland would not have had to manufacture salt. As animals became domesticated and grain became more important, however, salt production became essential.
We know from the annals that salt was an important and prized trade good in ancient Ireland. Evidently, most of their salt was derived from evaporation at coastal locations. There are many salt pans (low places were the salt water could be trapped at high tide or stored, and where the water could evaporate over time) recorded on old maps and a few of these are pans are carved out of the rock in various places (such as at Balycastle in Co. Antrim, where the engineering was relatively elaborate). The 8th century text Conall Corc and the Corco Luigde records that the Aran Islands paid a tribute of salt to the King of Cashel, their overload. This would presumably have been evaporated sea salt. There are placenames and map notations all over the island that records salt pans. For example, William Bald’s 1817 map of Co. Mayo shows salt pans at Polranny, near where the bridge to Achill Island now stands.
Although salt mines were uncommon in ancient Ireland, there are mentions of salt being occasionally dug from pits here and there along the coast. (Mining however, was not unknown in Ireland, in fact the South-West of Ireland would have been one of the earliest centers of copper mining during the bronze age. The early Celtic settlers would have arrived with great experience in both mining and salt production.) The one location where there has been (and remains) a large volume of rock salt is at Kilroot, near Carrickfergus in Co. Antrim. The deposits in this location were likely formed when a large body of salt water became cut off from the sea. Over time the water evaporated, and the salt was buried under layers of sediment and rock. In the 1850s, a surveyor searching for precious metals discovered a thick layer of rock salt under about 600ft of rock. The salt was initially removed by pumping water down shafts and pumping the resulting brine mixture back up, before evaporating the water to leave salt crystals behind. As mining technology advanced, shafts were sunk in the late 1800s. The mine is still in operation, supplying rock salt for roads in Northern Ireland and the UK.
In 1300, Ireland was exporting salt to supply’s Edward I’s army in Scotland. However this appears to have been an special effort on the part of the Norman barons to support Edward’s war, rather than reflecting the regular balance of trade. In the later middle ages, it’s recorded that salt was imported into Ireland — at least by the upper echelons of (Anglo-Irish) society, who could afford it — with English salt naturally being considered the finest. The placenames around the coast bear testament to the small-scale and localized nature of salt production in Ireland: there’s a Lough Salt in Co. Donegal (which may have had salt pits or deposits nearby, rather than being a salt-water lake); Salt Island on Strangford Lough; the Saltee Islands off the coast of Wexford; Salters Grange in Armagh; Salthill in Co. Galway; and Saltpans townland in Co. Donegal, among many others.
The historical reality of small-scale, localized salt production is apparently beginning to come full circle, with a couple of boutique sea salt producers starting up around Ireland. The latest, The Achill Island Sea Salt Company, was formed earlier in 2013, in an effort to restart this ancient local industry on Achill Island, where William Bald’s map bears testament to traditional salt production. The first Irish sea salt producer, Irish Atlantic Sea Salt, was started on the Beara peninsula in Co. Kerry in 2010.