Quartz is a hard crystalline mineral found in abundanceacross the globe in a variety of forms. It is the most common mineral on earth, making up 12% of the earth’s crust by volume, and is used in a wide variety of applications including jewellery, scientific research, manufacturing, and building. Owing to its varied uses, quartz is also an important mineral. Moreover, some rare varieties of quartz are considered to be quite valuable. It can also be quite beautiful, especially when cut and polished by a jeweller who understand the properties of quartz well. It is often used as a cheaper substitute for fancier gems, and when handled well, it can be difficult to distinguish from other expensive counterparts.
A quartz clock is a clock that uses an electronic oscillator that is regulated by a quartz crystal to keep time. This crystal oscillator creates a signal with very precise frequency, so that quartz clocks are at least an order of magnitude more accurate than good mechanical clocks. Generally, some form of digital logic counts the cycles of this signal and provides a numeric time display, usually in units of hours, minutes, and seconds. Since the 1970s, they have become the most widely used timekeeping technology.