Quartz or quartz is a mineral formed by silicon oxide.
Quartz is an English term used to name quartz , a mineral that is made up of silicon oxide (a compound also known as silica ). It is one of the most abundant minerals on Earth , since it can be found in sedimentary, metamorphic and igneous rocks.
Different varieties of quartz appear among the so-called precious stones . The variety most required for jewelry is amethyst , which is usually violet in color. Amethyst is generally among the most valued stones behind rubies, emeralds, diamonds and sapphires.
Citrine , ametrine and morion are other varieties of quartz that are used to create jewelry and ornaments.
Types of rocks
Let's see below a brief definition of each of the types of rocks, to better understand the concept of quartz:
- Sedimentary rocks : their formation takes place when sediments accumulate, that is, particles of various dimensions that transport air, ice or water and undergo chemical and physical processes , from which consolidated materials emerge. Some of the places where it is possible to find sedimentary rocks are the mouths and banks of rivers, the bottom of seas, lakes, valleys and ravines. Regarding their arrangement, they form strata or layers.
- Metamorphic rocks : these are those that are formed when other rocks, which can be of any of these three types, go through a process called metamorphism , either by exposure to high values of pressure, temperature or an active fluid capable of generating changes in its composition and provide it with new substances. The previous state of the metamorphic rock, and also the rock itself, is called a protolith. The classification of metamorphic rocks is carried out taking into account their texture and the minerals that compose them.
- Igneous rocks : these are those that arise after the cooling and solidification of magma . If the first of these processes occurs below the surface and slowly, rocks with large crystals called intrusive or plutonic are produced, while if it takes place on the surface and takes a short time (such as happens after a volcanic eruption), The rocks that form have microscopic crystals and are called extrusive or volcanic . Some of the best known, among the more than 700 that have been discovered, are porphyry, basalt, rhyolite and granite.
As we have indicated, quarts can be found in any of these rocks.
Watches usually contain quartz.
Characteristics of quartz
Colorless in its pure state, quartz stands out for its hardness . It can be used to generate various types of products : watches, radars and optical instruments are some of the objects that use quartz, which is a mineral with pyroelectric properties (temperature changes generate an electric field inside, altering the electrical polarization) and piezoelectric (the mechanical tension causes the electrical polarization of the mass, creating a surface potential difference).
Among these products, the most popularly related to quartz is the watch . In this case, the use of a piece of quartz is intended to produce pulses at equal intervals to measure time accurately. Typically, this piece is carved in a laminated form and placed in a metal cylinder, which protects it. To generate a vibration in the quartz crystal , it is necessary to feed it with an electric field.
Different classes
Based on its structure , it is possible to differentiate between a -quartz (or low quartz ) and ß-quartz ( high quartz ).
The first, which resists up to 573°C , has a trigonal type structure. From this temperature and up to 867°C , there is high quartz, with a hexagonal structure. Once above 867°C, quartz becomes tridymite , another type of mineral.