Many websites such as Mercola claim that Himalayan Crystal Salt provide many health benefits over regular sea salt. Is there evidence to back up those claims, that it's healthier?
Salt is entirely mineral based, so these are the only micro-nutrients of concern.
I could find a few articles containing a spectral analysis of various salts. Here is one for Himalayan pink salt:
Here is the best comparison I could find, it's mostly just a summary, I couldn't locate the raw data:
Of note is that while some of the coloured salts may contain higher amounts of essential elements, they also contain higher amounts of harmful elements. Although we're generally talking less than one part per million, so not enough to be of a concern, especially given the small amount you'd ingest. It's this mix of elements which gives the salts their colour.
All of these essential minerals are available in other foods, often in much higher amounts, especially considering the small amount of salt that it's recommended to have in a healthy diet. Perhaps the best salt to use is an iodised salt, especially if your food is coming from areas where levels of iodine in the soil are too low for the adequate intake, although iodised salt is also quite common in bread and some other processed foods now.