see how its harvested from dry sea beds, but how to actually make it, instead of harvesting it.

thats what i dont know.

but if its harvested from dry sea beds, how do they extract the other minerals out & leave only sodium?

thinking of the salt flats dried ocean beds they extract Sodium Bicarbonate from.

the Bicarbonate is from millions of years, trillions of plants & critters living & dying to accumulate the carbon bound to minerals, and dried into dust.