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So, I was doing some research on bonding and electronegativity and one of the examples used was NaCl (Sodium Chloride) which is salt. We don't buy processed salt, rather we buy salt from the Himalayas.

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Apparently this is better salt because it is not processed, made, etc. But, is there a difference between NaCl and Himalayan salt in regards to their molecular structure?

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    $\begingroup$ Exactly why would processing something to make it consistently pure and free from potentially dangerous ingredients make it worse? $\endgroup$ – matt_black May 12 '16 at 18:18
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    $\begingroup$ @matt_black "better" can mean a lot of things. It could have better taste, less environmental impact, etc. (I don't know if it does, just giving examples). It's not clear to me what OP meant by it. $\endgroup$ – Era May 12 '16 at 19:13
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    $\begingroup$ Typically, the people making claims like "Apparently this is better salt because it is not processed, made, etc." are the ones selling the stuff. A little skepticism is warranted. $\endgroup$ – ceejayoz May 13 '16 at 0:30
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    $\begingroup$ I'm guessing one important difference is the price. $\endgroup$ – MPW May 13 '16 at 3:29
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    $\begingroup$ @matt_black processing or purification can add impurities of chemicals used to purify the desired chemical, e.g. organic solvents, metallic catalysts etc. So it can happen that you removed one impurity and added the other. Of course, I don't want to get into regulations of food processing here, but it is a thing to consider $\endgroup$ – Alexandria May 13 '16 at 7:01
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No salt will be pure NaCl. Each will have some degree of other elements. The fact that the salt isn't white confirms there are other elements present.

See Analysis of Gourmet Salts for the Presence of Heavy Metals which investigates 14 salts including two Himalayan salts.

See especially "Table 3. Comparison of toxic elements in Table Salt".

A "Himalayan Pink Fine Mineral Salt" was found to have the highest level of cadmium and tied for first for the highest level of nickel.

NaCl isn't molecular, but instead is a lattice of Na+ and Cl- ions. Other ions can lie within this lattice as impurities.

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    $\begingroup$ Wait, so Himalayan salt is more toxic than processed salt? $\endgroup$ – mematusz May 12 '16 at 17:52
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    $\begingroup$ @VPrime not necessarily, but if it isn't white or colorless it's obvious that there is other stuff in there. The reference says in the toxic elements section "highest concentration of elements were found in the darker or deeply colored salts". $\endgroup$ – DavePhD May 12 '16 at 18:02
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    $\begingroup$ @Era It's somewhere between 97% and 99.7% pure. We have another question about that chemistry.stackexchange.com/questions/24816/… $\endgroup$ – DavePhD May 12 '16 at 19:22
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    $\begingroup$ @CarlosCarlsen “NaCl” refers a molecule composed of one sodium atom, and chlorine atom, and nothing else. A substance is “purely” NaCl when it consists of only this type of molecule, and nothing else. So when you ask “is NaCl more ‘pure’?” the answer is, by definition, yes—you have defined the substance as being of a particular type of molecule, and have indicated that this is all it is composed of. But you seem to be using “NaCl” to mean “processed table salt” which is not quite true: processed table salt is mostly NaCl, but nothing in practice is 100% pure, plus many places add iodine. $\endgroup$ – KRyan May 13 '16 at 14:34
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    $\begingroup$ @CarlosCarlsen So table salt is mostly NaCl, possibly with some iodine, and then very small amounts (0.3% - 3% to use DavePhD’s numbers) of whatever else. It is therefore 97% “pure NaCl.” And since NaCl is white, something that is 97% NaCl is probably white (and is in the case of table salt). Something like the Himalayan salt, that is mostly NaCl but visibly not white, must have some larger amount of something else to give it that color: it must be less “purely NaCl” than table salt. So yes, the color of the Himalayan salt indicates that there is more than just NaCl molecules in it. $\endgroup$ – KRyan May 13 '16 at 14:37
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You've already fallen to the marketing. Take a step back and ask yourself - how would a processed X be better then natural X? In many cases, you'll find advantages and disadvantages to both approaches. And don't forget that "natural" can kill you just as easily as "industrial" - you don't even have to go to outright poisions like death caps. A lot of the food we eat all the time is poisonous without proper processing - potatoes or rhubarb, for example. In other cases, we're outright trying to get those poisons in our food - chocolate, coffee, tobacco; of course, we're calculating how much of the poison is appropriate to get the desired behaviour (good taste, "drug effect") while limiting damage. Humans are actually pretty tolerant to huge amounts of different poisons - the ones that are left are usually very serious indeed :)

But you can be sure that "molecular structure of NaCl" will always be the same - it's entirely determined by the laws of physics. There's been some crackpottery about ideas like "water memory" or "changing angle between atoms in water" - that's just pure hogwash playing on people who didn't pick up much of Chemistry in high school, so I feel I have to stress that. What might be different is composition (impurities in addition to the NaCl) and crystal structure (pure NaCl in a well made crystal is very optically transparent, the pink colour of Himalayian salt is due to impurities).

Processed salt in particular is something humans have done for thousands of years (in fact, the ancient Greeks and Arabs burned oil for salt processing :)). The technologically simplest way to make salt is by letting salt water evaporate - this was commonly used in places where sunlight and other power sources (mostly rock oil) were plentiful. However, salt water is far from being pure NaCl indeed - there's plenty of other salts involved, as well as various other contaminants. These contribute to the colour and taste of the salt produced.

The purest "natural" salts were formed when whole seas evaporated - in Europe, this is mostly the Middle-terranean, of course. That was the source of many salt deposits that were extensively mined in Europe. Since such huge volumes and areas evaporated, the different salts precipitated out of the solution at different times and in different places, so you'll find quite pure "rock salt" formations - 85% and upwards is quite typical.

"Refined" salt is produced by purifying salt sources - the resulting salt might be up to about 99.75% NaCl or so. The source for the refining might be anything from sea water to rock salt to "whatever salty thing came by".

So unless the refining process itself introduces harmful impurities, refined salt will be much more pure NaCl. Is that a good thing? I don't know. There's certainly nothing inherently good or bad about purity - perhaps the other impurities are useful (iodine); perhaps they are harmful (kidney stones fun :P). And that's what you should think about when considering marketing claims such as "Himalayian salt is better because it's not processed". Processing is generally a good thing - you probably prefer your meat cooked, and your vegetables devoid of E. Coli, don't you? Just like home processing, industrial processing can make things better or worse, or a mixture of both. That's just the way the world works :)

If you find that you like the taste of Himalayian salt, that's the impurities talking (assuming you can actually tell the difference from a placebo). Nothing inherently bad about that, enjoy yourself ;) And don't forget that it can also be human-made for a good bit of profit :P

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