Answer:
True
Explanation:
Quartz is a mineral that abounds in the earth. It is the most common on the earth's crust after feldspars. The basic composition of this mineral is given by the important presence of silica. We can find it in igneous, metamorphic and sedimentary rocks. Quartz has numerous specific applications within the industry and jewelry. The exploration for its later commercial exploitation is simple, since it is easy to recognize with the naked eye.
This is a mineral of varied origin. Quartz crystallizes directly from magma, when its origin is magmatic it separates into irregular grains, an example of them are granites. During hydrothermal formation, it is the mineral that appears in reefs of greater propagation.
It is present in plutonic rock as well as in hypoabisals (pegmatites and porphyry). Most rocks have quartz as one of its components.
Its chemical formula is SiO2 being its name from the elements that compose them, silicon oxide and this compound is the only one that must be present, any other element or compound is considered an impurity.
By its structure we can distinguish two varieties of this mineral: quartz-α and quartz-β. The first one is known as low quartz, its structure is trigonal and can exist in temperatures up to 573 ° C. Once this thermal mark has been overcome, it is transformed into quartz-β, whose structure is hexagonal and is thus maintained until 867 ° C. After that mark it becomes tridymite, which is also an oxide mineral, but class 4.
The quartz has a transparent white color, although in some occasions it can present reflections or veins pink, reddish and even black, depending on the impurities. It has a hardness 7 on the Mohs scale and its fracture is concoid. Its density is 2.65 g / cm3 and at 1713 ° C it reaches its melting point.
One of the properties that stands out the most is its resistance to weathering. This means in geology that a mineral that has a specific structure in the depths of the earth, such as the lithosphere, is not altered on the surface, in contact with the atmosphere, the hydrosphere and the biosphere.
Quartz has piezoelectric properties, that is, the ability to acquire an electrical polarization of a crystal when subjected to a mechanical pressure in its mass. Directly related to the described property, it also has pyroelectric properties, that is, the ability to acquire an electric polarization, produced by temperature changes.
