I have recently started doing a lot of research on the piezoelectric effect with the hopes of gaining a better understanding of the topic. When I can I like to do experiments on top of reading because it helps cement the knowledge I learned more effectively. The main topic I am looking into right now is quartz crystals. I have researched the molecular structure of quartz and what causes the piezoelectric effect but I am having a hard time finding out how the shape effects the frequency. I have mostly found resources on what makes small perfectly made factory quartz crystals oscillate but I have not been able to find any information on the processes of natural quartz.
The main thing I hope to gain from your knowledge is the understanding of how natural quartz crystals behave when a force or voltage is applied to them. I have a collection of quartz crystals ranging in sizes but I cant complete any successful tests with them on a larger scale.
Question 1- What effect would a force have on a cluster of natural quartz crystals? I ask this because the molecular structure would be intertwined so I wonder how it would be polarized when a force is applied and what kind of oscillation would be caused. Also how much would the efficiency drop by when compared to a perfect set of quartz crystals?
Question 2- When I have a single quartz crystal that is not uniform how can I determine its internal lattice structure to best predict its poles for any possible experiments I may conduct? I have been unable to read any voltage being created when a force is applied to any of my non uniformed crystals.
Question 3- I know that irregular quartz crystals with deformations will be less efficient but is it even possible to apply a force and read a return voltage with conventional tools and if so how would this best be done with that larger set of crystals.