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Many barbeque lighters use a piezoelectric crystal to create a spark to ignite a gas such as butane. When the crystal is used in this way it is often refered to as a piezoelectric ignitor. The source of the gas is contained within the lighter body. If you remove this piezoelectric crystal while keeping the trigger mechanism and wires attached, you can see that it creates a spark around 7mm in length. This is in the kilovolt range.

Extracting a Crystal from a Lighter

I needed such a crystal so I purchased one of these lighters and removed it as the following pictures show. Care must be taken in taking it apart since there is a flamable liquid under pressure here. I first kept lighting the lighter until it wouldn't light anymore in order to decrease this pressure. Note that this decreased the amount of fluid by only half so care must still be taken after this point.

The lighter. Note that this has been reassembled for purposes of taking this picture but without the trigger. But this illustrates what you should look for in the stores.
Here it is after disassembly (trigger and crystal not shown, see pictures below for these). You basically pull off the long black part. Then you pull off the shorter black part. The part with the flamable liquid is on the right. You have to CAREFULLY cut this away while splitting the remaining body part as the picture below shows.
Here is it with the body split apart. At this stage you can remove the trigger and crystal.
The trigger and crystal. At this point you can hold the ends of the wires about 7mm apart and work the trigger. When you do, you'll see a part between the wire ends. If you don't get a spark then you're probably shorting the wires with your fingers where you're holding on to the crystal. Move your fingers away from the wires.
The crystal is the light olive colored part that the wires connect to. In the Testing section below you can see the crystal.

Testing the Crystal

I didn't make any measurements or take pictures with the kilovolt spark. However, having extracted the crystal, I did some simple measurements hitting it in other ways.

Actually, the crystal is a cylinder embedded in the rectangular plastic and epoxy body so you never see it. On one end is a small metal ball. This is the end you hit. The pressure is applied on the same axis as the polarity. Here I'm flicking it with my fingernail.
This is the resulting 4.16 volts as a result of the flick with my fingernail.
Here I'm hitting it against the table top.
This is the resulting 240 volts as a result of hitting it against the table top. Note that I've seen voltages as high as 500 volts, the highest my oscilloscope will show.

Piezoelectric static electricity generator

You can turn your ignitor into a piezoelectric static electricity generator.

As stated above, with the wires separated about 7mm apart you get a spark between the two sharp ends of the wires. Very roughly, that's 21,000V, assuming 3000V per mm. But what if those ends weren't sharp and were separated by more distance? Make one end be a smooth metal ball. The other end, the earth electrode, is the long black part in the 2nd photo above. Now, instead of a spark, the positive and the nagative charges (the high voltage) remains on the two electrodes. Using one hand, touch the earth electrode with one finger and move another finger close to the ball. A spark should jump to your finger. You may have to sand off the part of the earth electrode that your finger will touch in order to get good electrical contact.

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