Saltverk: Icelandic Flaky Salt Made with Hot-Spring Heat

Saltverk makes flaky sea salt at Reykjanes, a small peninsula on Ísafjarðardjúp, the long fjord that cuts into Iceland's Westfjords, and every stage of the work runs on hot water from the ground. The company pumps seawater from the fjord, concentrates it into a brine, boils the brine until crystals form and then dries the salt. The maker says geothermal energy is the only energy source in the process. A royal salt works tried the same idea on the same peninsula in the 18th century and closed after about two decades. Saltverk has made salt there since 2011. The finishing salt guide covers flaky salt as a style, and Harvesting Salt covers the other ways sea salt is made.

The first salt works at Reykjanes

Vísindavefur, the University of Iceland's science website, writes that the Danish king started salt production on the peninsula in the latter part of the 18th century because he wanted to build up industry in Iceland. Seawater was channeled to the hot springs, where it boiled away and left sea salt behind, and the salt was used, among other things, for salting fish. Vísindavefur calls it probably the first use of Icelandic geothermal heat for industry. Húsaflutningar, a website that documents Icelandic buildings that have been moved, dates the works to about 1773 to 1793. Its page on Betuhús, one of the salt works' original houses, lists what was built: two houses, one for the manager and one for the salt workers, five or six boiling houses, two drying houses, a large salt house, a house over a seawater tank, two pump houses, a water wheel and wooden pipes.

The works did not last. According to Vísindavefur, the salt-making itself went fairly well but returned little for what it cost. Húsaflutningar gives a second reason. The salt took up lead compounds from the pans, and fish salted with it turned bluish, so it was hard to sell. The history of salt explains why a kingdom would build a salt works on a remote fjord in the first place.

Who they are

New Hope, the natural-products trade publication, reports that Björn Steinar Jónsson studied engineering and worked at IBM in Copenhagen, where, in his words, he was surrounded by the New Nordic cuisine movement, and that restaurants like Noma inspired him to start Saltverk. He founded it in 2011, and the maker describes the company as having re-established salt-making in Iceland. Visit Westfjords, the regional tourist board, gives its address as Reykjanes, 421 Súðavík. Reykjanes itself was built up as a school for the children of the area, placed there for the hot springs and easy access by boat. It is now a hotel and campsite, with a geothermal pool the board calls Iceland's longest. The pool was meant to be 50 meters and was built a little longer by mistake. New Nordic in a Bottle covers other pantry makers that came out of the same movement.

How the salt is made

Seawater from Ísafjarðardjúp, where in the maker's words the North Arctic Ocean stream goes down the bay, is pumped to open pans and preheated until it becomes a strong brine of 17 to 20 percent salinity. New Hope reports that the brine is then evaporated in open pans to about 28 percent, the point where it starts to crystallize. The brine boils until white crystals appear on the surface, and the maker describes the flakes as pyramid-like. New Hope reports that workers rake them out by hand twice a day and that Saltverk's three pans yield about 450 pounds per harvest. The salt is then dried, also with geothermal heat.

The maker gives the water temperature as 206°F, or 93°C, and says it runs under the pans. Vísindavefur says water close to 100°C comes up at Reykjanes. Because geothermal heat is its only energy source, the maker says, the process leaves zero carbon footprint, with no CO2 or methane emissions. New Hope reports that the salt carries the Climate Label from the Change Climate Project.

How much seawater goes into one jar

NOAA puts the average salinity of seawater at about 3.5 percent, or 35 grams of dissolved salts in every kilogram. Set against the maker's brine concentrations, that figure gives a rough idea of how much water the hot springs drive off for each 90-gram jar.

The table is an idealized estimate. Not all the dissolved salts in seawater are sodium chloride, and no pan recovers every gram, so the real figure per jar is higher than two and a half liters. Either way, the hot springs evaporate well over two liters of water for every jar.

The five salts

All five salts start from the same flake, and the maker says they contain no anti-caking agents or additives. The flaky salt's product page says every batch is third-party tested for heavy metals.

The flaky sea salt (shop flaky sea salt) is the one to learn first. It goes on at the table, after the cooking, so the crunch survives. The salting piece explains why grain size changes how salty a pinch tastes. The lava salt (shop lava salt) is mostly for looks. The maker says the charcoal rounds the salt's edges for a smoother, less bitter result. Black flakes show up well on pale fruit or a white soup. The birch smoked salt (shop birch smoked salt) is, in the maker's words, smoked over Icelandic birch wood in the way of old Icelandic tradition. The Arctic thyme salt (shop Arctic thyme salt) is, in the maker's words, floral and herbaceous, with a lavender-like scent. For the seaweed salt (shop seaweed salt), the maker describes a natural umami depth from the dulse and kelp.

The white flakes also finish sweets. The caramel guide covers salted caramel, and the Brittany piece covers the salt-and-butter coast most associated with it.

Storing it, and visiting

The maker says its plain salt keeps indefinitely and its flavored salts keep their quality for five years. The salt storage piece explains why salt clumps in humid kitchens and what to do about it. Visit Westfjords lists public tours of the salt works at 10:00 and 15:00 each day from 15 June to 30 August, with no booking needed.

The Saltverk salts ship nationwide from theambrosianpantry.com. The shop is at 263 Josephine Street in Cherry Creek, Denver, and visitors can ask staff questions in the shop.

Sources & Further Reading

• Saltverk: story; the 18th-century salt works, the 2011 founding, the brine, geothermal water at 93°C
• Saltverk: flaky sea salt; process, ingredients, heavy-metal testing, shelf life
• Saltverk: lava salt; activated charcoal
• Saltverk: birch smoked salt
• Saltverk: Arctic thyme salt
• Saltverk: seaweed salt
• Saltverk: all salts; the maker's suggested pairings
• Vísindavefur, University of Iceland, 6 August 2015: geothermal heat in the Westfjords and the Reykjanes salt works
• Húsaflutningar: Betuhús, Æðey; the Reykjanes salt works buildings and the lead in the pans
• Visit Westfjords: Saltverk
• Visit Westfjords: Reykjanes
• New Hope: Saltverk crafts sustainable Icelandic sea salt
• NOAA Ocean Service: why is the ocean salty
• The Pantry Dispatch: Finishing Salt, The Complete Guide to Flaky Sea Salt