Quartz
Quartz is a form of Silica (SiO2) and is the most abundant mineral in the Earth’s crust. It is used in optical and scientific instruments and in electronics such as quartz watches.
Quartz watch
Inside a quartz clock or watch, the battery sends electricity to the quartz crystal through an electronic circuit, causing it to oscillate at a frequency of 32768 times each second. The circuit counts the number of vibrations due to the oscillations and generates regular electric pulses, one per second.