What is quartz?
Quartz is a crystalline mineral, silicon dioxide, that is found in abundance in the earth's crust and is the principal component of sand. The quartz used in watches is synthetic, or man-made. Watch manufacturers use synthetic quartz crystals rather than natural ones because they have more consistent properties.
Where does the electricity come from?
In most quartz watches, it comes from a battery.
How does a quartz watch work?
The tiny piece of quartz serves as the watch's "oscillator." All timepieces have an oscillator of some sort- an object which, through its continuous, unvarying motions, "tells" a watch or clock how much time has passed. The oscillator in a grandfather clock, for instance, is a pendulum.
Quartz is an ideal material to use as an oscillator. First of all, it loses very little energy as it vibrates, so the vibrations are extremely steady. Secondly, it exhibits what scientists call the "piezoelectric effect," meaning that it vibrates in response to an electric charge and, conversely, generates voltage when it vibrates. This quality is central to the way a quartz watch operates. Here's how it works:
I. The quartz oscillator receives an electrical charge from an integrated circuit, which gets its power from the watch battery (or, in the case of a battery-less watch, the poser storage cell). The electricity makes the quartz vibrate, or oscillate, at the rate of 32,768 times per second. (Quartz crystals can be cut to vibrate at a huge range of frequencies. the bigger the piece, the slower it vibrates.)
II. As the quartz oscillates, it sends electrical pulses- at the same rate of 32,768 per second- back to the integrated circuit. A device called a "trimmer" regulates the quartz oscillations.
III. The IC "divides the electrical pulses repeatedly until they have been reduced to a single pulse each second. The circuit is, in effect, counting the pulses and returning to zero each time the count hits 32,768.
IV. If the watch is an analog model, the one-second impulses are transmitted to a stepping motor, which transforms them into mechanical pulses that drive a chain of gears and, ultimately, the watch hands.
The below pictures lists all the major components of a quartz movement.
2.) Integrated circuit or microchip
3.) Quartz oscillator
4.) Electric Stepping Motor