I think I have to agree with you on this one. Salt is salt. NaCl, Sodium Chloride. And it all comes from the ocean; even the stuff that gets mined deep underground originally was deposited by evaporation by some ancient sea. And I expect whatever minerals are found in sea salt today will survive millions of years of underground storage just fine. I imagine when salt is refined for table use it is just re-evaporated and ground up so it will be of uniform grain size and white and the mud, sand and silcates like foram shells removed. Silicon dioxide, SiO2, the main constituent of sand, foraminifera and diatom skeletons, is not water soluble (it's just another name for "glass", so nothing metabolizable by the human body is sacrificed.

Now I remember when I lived in Mountain View, the old salt evaporation ponds behind Shoreline Park and Moffet Field used to have some pretty bizarre colors, due to high concentrations of bacteria feeding off rotting organics in the stagnant brine. The organics were mostly dead South Bay plankton, assorted bottom fauna, salt water pond scum and migratory bird poop (it's a major stopover on the Pacific Flyway). It's my understanding this salt was primarily harvested for spreading on icy roads (it's gray color when dried out made it pretty unappetizing). It's smell when moist made it even more unappetizing. I imagine it now graces many a surburban yuppie table and frou-frou Palo Alto restaurant, instead.

PS: What's a shaved Himalayan? Does that have anything to do with the Dalai Lama?