I have no idea if there is a factual basis in this or not, but I often find that, if my eyes are closed and I pay careful attention, I can often feel things near me without touching them. I often walk around the house with my eyes closed, enjoying the exercise of avoiding chairs, toys, and scattered odds and ends - you can't say I'm memorizing the area, because my kids keep rearranging everything.
It doesn't always work, but I'd guess often enough that there might be something to this - maybe slight changes in air pressure or something? Beats me.
But it doesn't have much to do with crystals.
That being said, I do 'feel' something with some crystals, rocks, and other things that isn't accounted for by proximity touch, as I have to actually hold the stone in question to get the appropriate sensation. I personally think it's either some as-yet undetected or misunderstood natural energy interference, or it's some sort of folk-psychology reaction, since I'm already fairly familiar with what various stones are supposed to do.
The strangest occurance I've ever had involving stones was with a piece of red jasper. I was told that this stone could absorb 'negativity', so I placed it at the door of our house (over the sill) for a month. Coincidentally, we had a much better month, and the person who we thought was trying to do us harm backed off a LOT.
Well, it's a nice coincidence, I thought, but I figured I'd keep playing along - and did as directed, burying the jasper in a bed of sea salt for a month to 'cleanse the stone'.
Imagine my surprise and rather outright shock to find that the salt had blackened where it touched the jasper! I mean, as if burnt, that black, and ashen! It was alarming and more than a bit disturbing - especially since the container it was in had been hidden in a place only I knew about, so I cannot suspect tampering; and since I can come up with no chemical reaction between sea salt, jasper, and environmental variables (such as humidity) that would have blackened the salt in this manner. If any of you have any reasonable explanations for this seemingly mystic occurance, I seriously would love to hear it.
(for further info, the salt and stone were in a sealed Tupperware container, one of those 4-inch wide, 1 inch deep round ones, stored under the basement stairs, in the dark, in a nook in the rock walls of the basement; the basement was fairly humid, but no nearby electrical or other energy-radiating sources to influence reaction; the sea salt was from a grocery store (beats me how 'pure' or whatever it was, I cook with it sometimes); the red jasper was fairly pure with a single amber-colored streak in it that I think was evidence of a faultline in the stone.
Anyway... I'm a woo, and prone to believing in such things. Still - I really would like a nice, easy scientific explanation of this weird reaction (which has now happened three more times out of twelve instances of burying in salt).