[Off-topic but I expect it will be of interest]
We use crystals in almost all our computing contraptions - ever wondered how crystals were made? Starting from lumps of quartz from Brazil, this old film shows the labour-intensive processes of selection, orientation, cutting, lapping and etching needed:

Crystals Go to War 1943 Reeves Sound Laboratories; Piezoelectric Quartz Crystals for Radio



(I tend to watch these things at 2x speed)
via Hackaday

Thanks for the link! I found that quite interesting.

At the end they said they were able to change the frequency of the crystal using X-Rays, any idea how that works?

I don't know. Wikipedia says some things about the effect but not the mechanism.