About Quartz


Quartz is the most common rock-forming mineral, composed of silicone dioxide (SiO2) and is an important constituent of the earth's crust. Silicon and oxygen make up approximately 74 percent of the crust’s composition.


Most solid substances are crystalline in nature. Sugar and table salt are in the familiar form of individual crystals, yet most crystalline solids are actually aggregates of many interlocking smaller crystals; such as ice chunks or metals. A crystal is a homogeneous body having the natural shape of a polyhedron. They are three-dimensional solids bounded by plane surfaces with angles specific to a particular substance.


Every crystal consists of atoms, molecules, or ions arranged in a three dimensional pattern that repeats itself regularly throughout the entire crystal. These fundamental geometric patterns are the crystal lattice. Quarts crystals are hexagonal while rock salt, by comparison, is cubic, which defines their familiar shapes.


Varieties of Quartz are classified as crystalline (e.g., amethyst, citrine, clear quartz) and crypto crystalline; which has microscopic size crystals such as chalcedony (e.g., agate, jasper, onyx.) or chert (e.g., Flint-the dark variety of Chert was used by primitive peoples to make knives and spearheads and lighting fires). Quartz is also the primary component of sand and sandstone.


Pure quartz is colorless and transparent, yet can be colored by impurities to yield beautifully colored variations such as: Amethyst (purple), Citrine (yellow), Rose Quartz (pink), and Smokey Quartz (smoky yellow to brown).



Piezoelectric effect - When compressed or bent, it generates a charge or voltage on its surface. If a voltage is applied, quartz will bend or change its shape very slightly. They produce an electric voltage when subjected to pressure along certain directions of the crystal. Because of this property, quartz crystal has important applications in the electronics industry for controlling the frequency of radio waves.


The spark emitted from a gas barbeque grill ignition mechanism, or a fireplace lighter is created by striking a piece of quartz, thereby generating an electrical charge from the mechanical pressure applied to it.

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When placed in an electric field oscillates at a constant frequency and is used to control devices that require precise regulation such as quartz watches and radios. Quartz crystals have been in regular use for many years to give an accurate frequency for radio transmitters, receivers and computers.


Quartz watches use this ability of the crystals to vibrate when an alternating voltage from an outside source, such as a battery, is applied. A typical watch battery consists of a single cell. It contains an electrolyte and electrodes that convert chemical energy into electrical energy. Quartz crystals are cut in specific ways to create resonators of almost any frequency. The frequency of the quartz oscillator is determined by the cut and shape of the quartz crystal. The most common watch crystals are miniature-encapsulated tuning forks which vibrate at over 32,000 times per second.


Quartz crystals exhibit a property called the piezoelectric effect, that is,

In 1926 WEAF, New York becomes the first commercial broadcast station to use crystal control. In 1939 The U.S. Military decided to convert its radios to crystal control.