Common Name: Celtic Salt

Although it is harvested in modern-day France, the name “Celtic salt” recalls the Celtic people of Brittany, who first systematized salt marsh cultivation in the region.

Alternate names are Sel Gris and Grey Sea Salt.

Scientific Name: Sodium Chloride (NaCl)

Editorial Note: This entry is part of The Culinary Compendium’s ongoing ingredient archive and will be expanded as new sources are examined.

History: Celtic salt, also called sel gris, is a mineral-rich, moist sea salt. It was traditionally harvested from clay-bottom salt pans along the coast of Brittany, France, specifically Guérande, which was historically located in Brittany, but became part of the Pays de la Loire region in 1941.

Celtic salt has been harvested in Brittany for over 2,000 years, with traditions dating back to the Iron Age. The process was refined by the Celtic people and medieval salt workers.

The coastal region of Guérande became famous for its vast salterns, a swamp of salt water about 1,700 hectares in size, where seawater is drawn through a maze of clay-lined basins and left to evaporate in the sun and wind.

Salt harvesting in Guérande is still done manually by paludiers (salt workers), who use wooden rakes and often work barefoot to gently collect the damp crystals.

It was highly valued in Medieval France, where it was used in cooking, currency, and trade. Unlike heavily taxed white salt under the Ancien Régime, grey salt was considered rustic and outside elite taxation, making it a salt of the people.

Interesting Facts: In Celtic folklore, salt symbolized protection and was believed to ward off spirits.

Uses: It pairs well with herbed butters and rustic breads or sourdough.

Selection & Storage: Quality Celtic salt is damp to the touch with a clay-like scent. Avoid Celtic salt that seems overly white or dry.

It should come from Guérande, Noirmoutier, and Île de Ré for authenticity.

Taste Rating: ★☆☆☆☆

Celtic salt has a subtle mineral-rich salinity with hints of earth and sea. It is best used as a finishing salt.

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