Crystals form in nature when molecules accumulate to stabilize, when the liquid begins to cool down and. This process is called crystallization and can occur when magma hardens or when water evaporates from a natural mixture as well. Some crystals have been formed by magmatic and metamorphic processes, giving rise to large masses of crystalline rock. The vast majority of igneous rocks are formed from molten magma and the degree of crystallization depends mainly on the conditions under which they solidified.
Rocks such as granite, which have cooled very slowly and under great pressures, have completely crystallized; but many types of lava spilled onto the surface and cooled very quickly, and a small amount of amorphous or vitreous matter is common in the latter group. Other crystalline rocks, metamorphic rocks, such as marbles, mica shales and quartzites, recrystallize. This means that at first they were fragmentary rocks such as limestone, shale and sandstone and were never molten or completely in solution, but the high temperature and pressure conditions of metamorphism have acted on them, erasing their original structures and inducing recrystallization in the solid state. Crystals can be formed in different ways.
Some mineral crystals form when pressurized molten carbon cools rapidly. If you want to see how crystals form, you can do a small project in your own kitchen and see the crystals forming with your own eyes. This can be done by putting a small amount of table salt in a little running tap water, wait 24 hours and you will see beautiful formations in cubes. This happens because water evaporates, bringing the atoms that make up salt (the mineral) and water closer together.
They will eventually form a small, uniform group of atoms. The closer they come together, the more visible the formation will be to the naked eye. Scientists can determine what mineral they are looking at based on the way crystals form. For example, selenite crystals larger than 10 meters are found in the Cueva de los Cristales in Naica, Mexico.
The epitaxy (from the Greek epi upon + taxis) reminds us that sometimes the best way to grow a crystal is on another crystal. Crystallography is the science that measures the crystal structure (in other words, the atomic arrangement) of a crystal. In 1999, the world's largest known natural crystal was a beryl crystal from Malakialina, Madagascar, 18 m (59 ft) long and 3.5 m (11 ft) in diameter, and weighing 380,000 kg (840,000 lbs). The piezoelectric property, in which a crystal acquires an electrical charge when squeezed or hit, makes crystals useful in everything from living room speakers to ultrasound scanners.
For example, a perfect diamond crystal would only contain carbon atoms, but a real crystal could also contain some boron atoms. Other, less exotic methods of crystallization can be used, depending on the physical properties of the substance, including hydrothermal synthesis, sublimation, or simply solvent-based crystallization. The crystals found in rocks usually range in size from a fraction of a millimeter to several centimeters in diameter, although exceptionally large crystals are occasionally found. In the last block of ice, each of the small crystals (called “crystallites” or “grains”) is a true crystal with a periodic arrangement of atoms, but the entire polycrystalline does not have a periodic arrangement of atoms, because the periodic pattern breaks at the boundaries of the grains.
A crystal or crystalline solid is a solid material whose components, such as atoms, molecules or ions, are arranged in a highly ordered microscopic structure, forming a crystal network that extends in all directions. It's possible to grow your own crystals at home or in a laboratory, but you also need to have a starting point for crystals to form. The fusion method excels in the manufacture of polycrystals, but it can also grow single crystals using techniques such as crystal extraction, the Bridgman method and epitaxy. .
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