From seawater to flake: how we make salt with geothermal energy

Our recipe has two ingredients: Arctic seawater and geothermal heat. Everything else is time and hands. This is how a pan of seawater becomes a jar of flakes at our saltworks in Reykjanes.

1. The seawater

The water comes from Ísafjarðardjúp, the large fjord next to Reykjanes, in a remote corner of the Westfjords far from industry and shipping lanes. A cold current from the Arctic Ocean flows down the bay. A long pipe draws the seawater from deep, cold water in the fjord and carries it up to the salt house.

2. The heat

Reykjanes sits on hot springs. Water comes out of the ground at around 206°F and runs through pipes beneath our pans. It is the only energy we use to heat, boil and dry the salt. Nothing is burned, so our carbon footprint in making the salt is zero. As far as we know, we are the only artisanal salt in the world made with 100% geothermal energy.

3. From seawater to brine

Making salt means getting rid of a lot of water. Roughly nine liters have to leave the pan for every liter that becomes salt. The seawater is heated slowly, moving through a series of pans as it gets stronger, until it becomes a brine with a salinity of 17 to 20%.

4. The flakes

In the final pans, each about the size of a king-size bed, the brine keeps steaming until white crystals form on the surface. They grow into thin, hollow pyramids and slowly sink. Slow evaporation is what gives the flakes their shape, and it cannot be rushed.

5. Raked by hand

We rake the wet flakes out by hand with metal rakes made for the job. A machine would break the fragile pyramids; a careful hand keeps them whole. The salt then drains in tubs for about half a day.

6. The drying room

Next it goes into a drying room that feels like a sauna, warmed with the leftover geothermal heat, and dries overnight. Before packing, every batch is checked by eye and by hand so only crisp, dry flakes go into the jar. Nothing is added and nothing is taken out: no anti-caking agents, no iodine, no bleaching. Every batch is also third-party tested for heavy metals.

7. Flavors

For our flavored salts, the finished flakes are smoked over Icelandic birch wood or blended with Icelandic ingredients like wild Arctic thyme, seaweed, licorice root or activated charcoal. Read about all six salts.

Built here

When Björn Steinar Jónsson started Saltverk in 2011, there was no off-the-shelf equipment for making salt this way. Björn, an engineer by training, designed and welded much of it with his team, and they learned the method by studying the old techniques and by trial and error. We have been making salt in Reykjanes every day since.

Want to see it? Read about visiting the saltworks, or taste it in our Pure Flaky Sea Salt.