Robert Newton, Research Scientist, Lamont-Doherty Earth Observatory

It's a very odd mineral. It only can get formed in the ocean.

The chlorine's coming from the volcanos at the bottom of the ocean, the sodium is washing off the continents with the rain water and in the ocean they complex to create salt.

There is a lot of salt in the ocean, but it's only about 3.5%, so what happens is that a piece of the ocean gets isolated from the world ocean and then sits there over thousands of years evaporates.

Wherever you have thick salt deposits, we can mine the salt, it's because there's been an ocean that's dried up and left behind the salt.

To get a meter thick bed of salt, you've got to evaporate about 60 meters of water.

Salt deposits are really fairly common.

In the Atacama desert in Chile, because the Andes are such a recent mountain building event, these salt deposits have stayed very close to the surface and it's therefore very inexpensive to get to them and move them because you can actually mine them with open pits instead of deep subterranean mining tecniques.

Brian DeForest, Terminal Manager, Atlantic Salt Inc.

Believe it or not, it costs more, to bring it from upstate new york, than to bring it from Chile.

The salt from Mexico's white, the salt from Chile is peach, Ireland's brown.

Well, it all does the same thing, just different colors.

The ships, on average, that come here, they're about 55,000 metric tons.

Usually it's not going out as fast as it is now. We will stock pile it.

The trucks going out they might take 18 tons to 40 tons.

The clamshell buckets hold about 30 tons. When there are 2 cranes, they do an average of 1,000 tons an hour.

In days like today, we are loading it right into the trucks as it is coming off of the ship.

Robert Newton, Research Scientist, Lamont-Doherty Earth Observatory

It's a little bizarre to see millions and millions of salt being mined in order to spread it on the roads.

You have to imagine water in the process of freezing.These little molecules, in the liquid state, they're just randomly organized, and as you get cold enough, the motions slow down to the point where the interactions between the molecules get strong enough that they start to organize themselves into a fixed crystal lattice and that's freezing.

Now imagine you have salt in that. So, as you cool this thing down, the sodium and the chloride ions get in the way you have to slow things down much further to get those intermolecular bonds strong enough, that the water will crystalize and push the salt out of the way,

Is it edible? I suppose it is, it had never crossed my mine to break open a bag of rock salt and put it on my eggs in the morning, but unless you got very unlucky, my guess is it would be alright.