How Do You Measure the Frequencies of Natural Crystals?

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Discussion Overview

The discussion centers on the measurement of frequencies in natural crystals, exploring the factors that influence these frequencies and the instrumentation required for measurement. It includes considerations of different types of crystals beyond quartz and the methods applicable to measuring their vibrational characteristics.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants propose that crystal frequencies depend on size, shape, cut, and purity of the crystal.
  • One participant suggests using sensitive vibration detection devices, similar to those used for sensing heartbeats, but does not recall the specific name of the equipment.
  • Another participant emphasizes the need for solid answers and expresses frustration with vague responses, indicating a desire for more direct information.
  • A later reply mentions that "crystal frequency" can refer to multiple concepts and suggests that mechanical resonant frequency can be calculated or measured by vibrating the crystal and analyzing the response.
  • It is proposed that a piezoelectric chip or speaker connected to a signal generator could be used to vibrate the crystal, with measurement via a microphone or ultrasonic transducer linked to an oscilloscope.
  • Participants note that the method of supporting the crystal during measurement can affect the resonance results.

Areas of Agreement / Disagreement

Participants express differing levels of satisfaction with the responses provided, indicating a lack of consensus on the clarity and usefulness of the information shared. There are multiple competing views on the best methods and instruments for measuring crystal frequencies.

Contextual Notes

Some limitations include the ambiguity of the term "crystal frequency," which may refer to different types of frequencies, and the dependence of resonance on various factors such as support method and crystal characteristics.

MaterSammichM
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If I am correct, crystal frequencies depend on the size, shape/cut, and purity of a crystal(?)
How can you measure (what instrumentation) the frequency/ies of a natural crystal (other than just quartz)?
 
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In the same way you'd measure vibrations in any other material.

Using a device capable of detecting vibrations - would need to be fairly sensitive. Sort of like the ones they use to sense heartbeats on lorries crossing the channel.

I can't, for the life of me remember the name of them.
 
Really?
I'm looking for solid answers and don't have time to read useless posts.
Your's really didn't help at all.
I knew that much on the subject.
Please... if all you want to do is hear yourself speak, do it in private, or at least write meaningless posts on someone else's thread.
 
Welcome to PF MaterSammichM.

You will soon learn that your attitude isn't acceptable here and people won't bother responding to you if you take that stance.

Google "vibration sensor" and you'll find a whole host of equipment capable of achieving your task. If you're too lazy to do this then that is your problem not mine.

Cut the attitude.

EDIT: Oscilloscope that's the one. You'll be need one of those too. Possibly something involving ultrasound would be a good choice.
 
MaterSammichM said:
If I am correct, crystal frequencies depend on the size, shape/cut, and purity of a crystal(?)
"Crystal frequency" is quite meaningless by itself. It can refer to (at least) several different things.

If you mean mechanical resonant frequency, you can either calculate it (if the shape is nice) or measure it by simply vibrating the crystal and measuring the response versus frequency. The frequency (or frequencies) where you get maxima of the response are the resonant frequencies.
You can vibrate the crystal with a piezoelectric chip or speaker attached to a signal generator and measure the response with a microphone, an ultrasonic transducer, etc., connected to oscilloscope.
There are some catches. The resonance depends on the way you support the crystal (at one end, in the middle, both ends, etc) as well as on the size, shape, material.
 

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