Well, from what I could see there was a small capacitor (ceramic fixed, in the picofarad range, if I can see clearly enough), a coil, what looked like a glass diode and I couldn't tell what those four things were around it- maybe diodes or chip caps? So what you have there is a tuned circuit. Is it imbedded or surrounded by the crystal?
So yes, if they all have the same value cap and coil (count the turns if you can and try to read the number on the cap) you can figure out the resonant frequency of it and see if it's the same for all of them.
If it's a transmitter, you're walking around with a frequency transmitter on you, which may be emitting frequencies in (hopefully) the kilohertz range (which is beneficial). Some healers use frequency generators in the kHz range for healing, but I don't know any more particulars.
I just got mine (actually didnt take long), I think Nyal has people helping with the trivial stuff like beading, while he does the delicate work. I definatly agree with that, I dont want him to begin hating the necklaces.
The four things surrounding it (and the ones in the middle) are groups of 3 bead looking things, on a circular copper wire. On on the groups the center bead is yellowish giving off an abalone type reflection, the two around it are grey/green (
oo
o), exept for the ones in the top-right corner which are purple, and the group of 3 in the center is inverted; the yelowish beads on the outside, the dark in the center (o
oo).
The brown capacitor thing says
33J.
The diode has some tiny cylinder (geranium?) with really tiny wires going in it, I can barely see them.
The coil has 9 turns.
The two contacts at the neck connect to the circuitry in the center.
The copper wire ring only touches at the one point at the bottom of the circuitry.
I put it on after meditating so I was more aware of energy. There was a small flow of energy at the contacts on my neck, I couldnt tell if it was to or from. This morning when I put it on the energy around my forhead started buzzing (not neccicarily because of the necklace).
I really dont think Nyal is doing this to make money, he put a lot of backbreaking work into them with a very large magnifying glass and very tiny tweezers. He definatly believes in them.
Edit: (2/23) I took it off before meditation. I was just doing Zen, shortly into it I had a mad energy rush from the back of my neck to the top of my head, somehow my head stayed on my shoulders

This is highly unusual during my sitting meditation. I switched to energy work right away. I was working on my forhead and there was the feeling of a giant stomping a huge iron spike through my 3rd eye and out the back of my head..... the giant felt like he had a little bigger boots than normal.
Also I feel more inclined to call or write family members (im usually horrible about communicating). Like my mom, I havent spoken to her in a long time. I was thinking I wanted to talk to her, shortly after she called; said she felt that she really needed to call me.
I'll add to this if anything noteable happens.