Actually, salt from the sea (and even from disolved underground sources - as in the often too salty - even for stock - in Aussie Artesian Bore water) can contain many more chemical salts than just pure NaCl. These "additions" are doubtless what the claims about 'salts for cooking/table use' having differing tastes are allegedly based on.

Some other 'salts' exist - "Epsom Salts" - Magnesium Suplhate (mostly): "Saltpetre" - as above, and a few others, including aluminum ones, also carbonates such as calcium carbonate (chalk. limestone). None of these are useful as edible table/cooking salt - some may even be poisonous.

"Spa waters" can contain a widely varying mixture of 'salts' - the so called "bottled waters" often are no different that the water you may find in your domestic tap. All natural occurring water - with the exception of freshly fallen rain - contains dissolved salts of one type or another.

And as for "Organic Salt" - oh, my ribs hurt with laughter - salt is an INORGANIC chemical....

Robin