Salmarincy — Sea salt as a food product: how it | salmarincy.com
Both salts are 97–99% sodium chloride; the real differences are crystal size, a small trace-mineral fraction and whether iodine has been added.
Start with what does not change. Refined table salt and sea salt are both 97–99% sodium chloride, and sodium is 39.3% of sodium chloride by weight. Five grams of either salt supplies about 2 g of sodium, and the WHO ceiling of 5 g of salt per day applies to both equally.
The compositional gap sits in the remaining 1–3%. In sea salt that fraction is mostly magnesium, calcium and potassium, left behind as seawater evaporates; refined table salt has no comparable listed mineral fraction. The gap is real on paper but small on the plate.
On narrow screens, swipe or scroll the plate sideways.
Crystal size is the difference you actually cook with. Fine table salt measures 0.3–0.8 mm and about 5–6 g per level teaspoon; coarse sea salt runs 1–3 mm and flake salt 1–5 mm wide. Swapping spoon for spoon across those sizes changes how much salt a dish receives, which is why percent-based recipes should be weighed. The Salt Crystal Size Chart page maps every grade in millimetres.
Iodine is a label question, not an origin question. Iodized salt carries 20–40 mg of iodine per kilogram, the WHO/UNICEF target for fortification programs, and either salt can be iodized. Sea salt's natural trace fraction is not a measured iodine source.
Best uses follow the geometry. Fine salt wins in baking, where bread dough needs 1.8–2.2% salt against flour weight and even distribution; coarse and flake salts win at the finish and in weighed dry cures of 25–30 g per kilogram. For pickling math at 2–5%, see the Brine and Salt Ratios page.
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