There isn't anything supernatural about working with crystals, all you are doing is aligning the energy fields around your body.
The claim that there is an energy field around people that can be aligned is a common claim of New Age/paranormality, and please be advised that it hasn't yet been properly demonstrated in any way: this field is, apparently, unmeasurable to known instrumentation, and yet is strong enough to be affected by things like crystal. So you will encounter some serious skepticism here about the very idea.
Consider a partially-blinded test: your partner sits down in a chair, blindfolded (and I mean properly blindfolded: preferably, blacken some swim goggles, so that she can't "peek"). You have a deck of cards, thoroughly shuffled, a quartz crystal, and a roll of quarters (or some other non-crystal object about the size of the quartz crystal). And you have an observer with a clipboard and a watch.
Procedure: your observer flips over one of the cards. It will either be black or red. He/she records the result and taps the table once. For one minute (by the watch of the observer), you "comb" your partner's "aura": with the crystal, if the observer pulled a red card, and with the non-crystal object, if the card was black. After a minute, you stop, and the observer taps the table twice. Your partner says "yes" if she felt that her "energy field" had been affected, or "no", if she did not. The observer records the response next to the card-draw result. The observer then draws another card, taps the table, etc -- the whole process is repeated at least 10 times.
There should be no talking other than your partner saying "yes" or "no". Try this out and see if your partner can successfully sense whether you're using the crystal vice something non-crystal (I'd say that if she gets 7 out of 10, there's probably something going on -- better math minds than mind can figure out the actual probabilities if you need them).
And bear in mind that this is an extremely rough, and not particularly thouroughly-designed test (it does not properly control for trickery). It also does not isolate the original claim ("there is a human energy field"); it merely tests whether your partner can tell whether you are using crystals or not (if she can't tell beyond random chance, then something else is going on: probably the placebo effect).
