From the food52 blog:
Himalayan Salt: Hand-mined from ancient sea salt deposits from the Khewra Salt Mine in Pakistan, Himalayan salt is rich in minerals and believed to be one of the purest salts available
How can salt (NaCl) be both "rich in minerals" and "one of the purest salts" at the same time. "Pure" means not having stuff in your substance that isn't the substance itself. If you are talking about salt, than minerals other than salt in your salt makes that salt impure.
Impurities might be good, but they are what they are.
I've been hearing about Himalayan salt now for several years, and it's always hyped as a miracle medicine that can cure you of essentially any ailment, and it can do it in a variety of ways. When some substance that is purported to actually exist somewhere is said to be able to cure you of anything, then it is helpful to ask about the health of the people living near the miracle substance. Nepalis who mine this salt do not, despite all the claims for this miracle drug, live forever.
And, by the way, most Himalayan Salt is mined in Pakistan hundreds of miles from the Himalayas.
God Bless Marketing.