What is quartz in simple words?

Quartz – the general name of one of the most common groups of minerals in the Earth’s crust (12%). Minerals included in the quartz group differ in their physical, mechanical and other properties, such as hardness, color, shape, deposit, etc. The origin of the word quartz has German roots but has multiple meanings. So, according to one version, it comes from him. “quarz” – solid; according to another version – from him. “querklüfterz” or «quererz”, which literally translates as “ore of secant veins”.

Physical and chemical properties of quartz

Quartz is a mineral with a crystalline structure. The crystal lattice of quartz is a hexagonal pseudo-hexagonal prism, and quartz single crystals have both left- and right-handed shapes. Depending on the rocks of what origin (igneous, metamorphic, sedimentary) quartz crystals are present, they may contain the so-called. “grains”, “veins”, “brushes” of other minerals. If we consider quartz in its “pure” form, i.e. without inclusions of other minerals or chemical elements, quartz is a colorless or white mineral. If quartz contains inclusions of other minerals or chemical elements, then the color of quartz is very diverse – from yellow (citrine) to black (morion). Quartz is characterized by a non-metallic luster, high hardness and lack of cleavage. From a chemical point of view, quartz is silicon (IV) oxide, chemical formula is SiO₂. Belongs to the group of acid oxides. Melting point – 1713-1728° C. Resistant to aggressive environments; able to dissolve in alkali melts, as well as hydrogen fluoride (hydrofluoric acid). Silicon (IV) oxide exhibits di- and piezoelectric properties. It is one of the main components of glass. Silicon (IV) oxide is characterized by the phenomenon of polymorphism, i.e. existence in several forms depending on temperature. Thus, α- and β-quartz are distinguished, existing at low and high temperatures, respectively. There are known modifications of quartz that are independent minerals: cristobalite, tridymite, coestite, stishovite.

Varieties of quartz

When we talk about “pure” quartz, we are talking about a variety of it called rock crystal. This type of quartz has no color and is transparent. Among the varieties of quartz, the most famous and widely used (in the production of jewelry): aventurine, agate, amethyst, morion, rose quartz, chalcedony, citrine, onyx, tiger and cat’s eye. Each of these minerals has a characteristic color and properties, for example, amethyst is a purple mineral, which is explained by the presence in its composition of a coloring organic substance of an unidentified structure. The yellowish color of aventurine is due to inclusions of mica, hematite, and sometimes iron hydroxides; the presence of titanium and iron determines the black color of morion, etc.

Quartz mining and production

Quartz was formed through various geological processes, mainly from magma. Quartz is found in sedimentary rocks – limestones, dolomites, etc. In coastal coastal zones, quartz occurs in the form of rounded pebbles. Quartz is part of sand. Quartz sand deposits play a special role in industry. Despite the widespread occurrence of quartz in natural conditions – nature, artificial methods for the production of quartz have been developed and patented. One such method is the hydrothermal method. According to mineralogy experts, artificial quartz is more homogeneous, and the distribution of impurities in it is more uniform than in quartz of natural origin. Piezo-optical quartz is obtained from quartz of artificial origin; it has also found wide application in the production of jewelry, since in this case it is possible to obtain quartz of any color and its required saturation (green, blue, dark blue). The largest production of artificial quartz in the Russian Federation is located in Gus-Khrustalny and Yuzhnouralsk. Artificial quartz in Yuzhnouralsk has been produced at the Kristall plant since 1962. The quartz produced at this plant was later used for the needs of the radio-electronic industry, and was also exported to other countries. The main industrial scale of production of sheet glass, glass containers, crystal and other glass products made from artificial quartz is also produced in Yuzhnouralsk at the OJSC Quartz enterprise. The largest native quartz found in our country is kept in the museum of the St. Petersburg Mining Institute. The mineral is over 1 meter high and was originally used as a city bollard.

Quartz in the history of mankind

In human history, quartz has been known since before our era. Thus, a product made of rock crystal – a vase (XVI century BC) – was discovered during excavations in Mycenae, a product made of morion – sunglasses – was found in the tomb of the Egyptian pharaoh – Tutankhamun, and quartz beads were discovered during excavations in Mesopotamia , during excavations of Mayan cities, a skull made of quartz was discovered. In Russia, one of the most unique products made from quartz (rock crystal) is a samovar, made especially for Peter I, in the USA – a crystal seal. The first of the products is in the collections of the Armory Chamber of the Russian Federation, and the second is in the US National Museum of Natural History. The National Repository of France contains unique drinking cups and an urn made of rock crystal and dating from the reign of Emperor Nero.

Applications of quartz

Quartz sand is used in the production of glass and various products made from it. It is used in optical instruments, in ultrasound generators, in telephone and radio equipment (as a piezoelectric), in electronic devices (a quartz resonator is a component of devices for stabilizing the frequency of electronic generators). Quartz is widely used in the production of jewelry. It is used in the production of watches and lenses.

Methods to confirm the natural origin of quartz

To distinguish natural quartz (quartz of natural origin) from artificial or glass (since the most rare varieties of quartz are often counterfeited), it is necessary to run a sharp or blunt object, such as a knife or stone, across the surface of the quartz, and if the quartz is of natural origin, then traces will not remain on its surface. Another way is if you lick the surface of a natural gem and artificial quartz with your tongue, then the surface of the gem will always feel colder. There are other methods, but they are usually used by jewelers.

Other Interesting Facts About Quartz

Geology
Minerals

December 14 2018

Quartz: types, properties, applications

Natural quartz

Quartz in a chemical sense is nothing more than silicon dioxide. The name “quarz” itself goes back to the German language, but the exact meaning of the word has not yet been established. The mineral has several names used by people: hair of Venus, hedgehog stone, arrows of Cupid. Quartz is also called “Mexican diamond.” Natural stone can have different shades: from transparent and translucent to piercing blue. The mineral is quite hard, with a Mohs strength index of seven. Quartz has a density EN 14617-1 of 2,2-2,4 g/cm³. The stone owes its origin to Africa, the main deposits being Madagascar and Brazil. The natural mineral is in demand in jewelry, as well as in the production of souvenirs and household items.

Natural quartz sand lies in water basins, being part of the soil. Most often the grains are small, 0,2-1 mm. The main way it is mined is through quarrying. The extracted particles are subject to sieving, washing and drying.

Quarry agglomerate

The scope of our company’s activities involves the use of natural quartz converted into quartz agglomerate. The following article will be devoted to this particular product.

Quartz agglomerate (other names are agglomerated stone or quartz stone) – consists of natural quartz sand and binding resins.

Vein quartz, crushed into crumbs, is cleaned, dried, and the fractions are sorted depending on size. The main largest suppliers of quartz from which quartz stone is produced are Israel, China, India, Türkiye and Russia.

Quartz agglomerate is produced in the form of slabs: sheets with strictly defined dimensions.

The technology for making agglomerate was invented in the 1960s by the talented Italian engineer Marcello Toncelli. Breton has patented this technology, which is still the most successful in the production of agglomerates. More than 50 factories around the world produce more than 40 million square meters of stone per year.

The product line of various manufacturers includes more than 1000 different colors and textures of stone. The required design is created by mixing quartz chips of various fractions with an admixture of pigments and decorative elements. The latter may include fragments of mirror, brass, mother-of-pearl; fragments of granite and marble, glaze and glass.

If the unique recipe of a stone in terms of its physical properties was developed a long time ago and is unchanged, then continuous work is underway on the design in special laboratories of the largest manufacturing plants. Every year new colors and textures appear that correspond to modern trends in interiors.

Sinter production process

Quartz powder and resin in powder form are added to the mixture of quartz chips, pigments and decorating elements. The resulting mixture is thoroughly mixed. Quartz powder prevents the occurrence of microvoids in the thickness of the material.
The mold is filled with the resulting mixture and sent to a vacuum vibropress.
Pressing under conditions of vibration and air pumping makes it possible to obtain a high density of the mixture.
Polymerization in a heated chamber where the mold is placed.
The cooled slab is given precise dimensions and the required surface texture: gloss, semi-gloss, matte, volcanic surface effect, and so on.

The production process ends with a quality control procedure.

The slabs always have the exact declared size, without deviations in geometry.

Properties of quartz stone

The composition and manufacturing technology of quartz stone provide the following characteristics:

Hardness. The content of 93-97% natural quartz provides the agglomerate with a hardness exceeding the hardness of granite.
Wear resistance. Resistant to mechanical damage.
Hydrophobicity. The complete absence of pores and microcracks does not allow liquids and contaminants to be absorbed into the thickness of the material. No natural stone for interior decoration has such properties. Unlike natural materials, agglomerate does not require regular preventive impregnation to protect the surface.
Hygiene and safety. Fungi, microbes and mold do not develop on the stone. There is no background radiation.
Attractive appearance. Quartz stone is visually and tactilely identical to natural rocks.

Quartz in the interior

Processing quartz slabs requires expensive high-tech CNC equipment, similar to equipment for processing natural stone.

80% of the volume of quartz stone is used for the manufacture of countertops and bar counters.

Quartz is ideal for surfaces subject to intensive use. It is almost impossible to cause damage with metal objects. The knife will leave a metallic mark on the surface of the quartz, which can be easily removed with a soft sponge.

The second most popular product made from quartz stone is window sills. The stone will ennoble the window opening. UV resistance will keep the original color and pattern of the stone unchanged. Stains from spilled liquid from flowers are easily removed without penetrating deep into the material.
Ease of use, wear and vandal resistance allow the use of quartz in cladding floors, steps and walls in private and public interiors. Due to its hydrophobicity, it is successfully used in wet rooms: bathrooms, bathrooms, swimming pools, spas. Quartz can be not only smooth, but also with various textured anti-slip surface treatments.

Stone care

Quartz is extremely wear-resistant and easy to use. However, there are a number of recommendations and limitations even for this material.

Avoid the following events that could damage your quartz product:

Heavy objects with sharp edges or corners falling onto the surface.
Placing objects heavier than 15 kg on the surface, especially on tabletop overhangs.
Cleaning the surface with products containing abrasive particles equal in hardness to quartz or harder. These can be abrasive sponges and liquids. It is enough to use a soft sponge and soap solution.
Placing a hot pan just removed from the stove on the surface. Quartz can withstand up to 180 degrees. And even more. Limitations are associated with decorating additives in the structure of the agglomerate, which do not have the properties of quartz.
Use of solvent and other aggressive substances with a pH greater than 10. Use of products containing hydrofluoric acid or chlorine, concentrated bleaches and solvents.
Use of degreasers.

Examples of foods to avoid:

Oven cleaners, acids for pipes and drains, solvents for varnishes and paints.

Daily Care

Quartz does not require special preventive impregnations, unlike natural stone.

The non-porous structure itself guarantees the absence of absorption of contaminants into the thickness of the material. Daily care consists of removing surface dirt using a soft sponge or brush with soapy water or plain clean water.

Old stains

For stubborn stains that sit tightly on the surface, it is recommended to apply a non-abrasive cleaner for about 10 minutes. After dissolving the stain, it must be removed with a soft sponge and wiped dry.

Hardened paint, varnish and other insoluble products can be removed using a spatula or knife. Precautions must be taken. Place the tool at a slight angle to the surface, do not press too hard. Traces of metal remaining on the surface can be removed with a sponge along with any remaining dirt.

Using hot cookware

Quartz stone can withstand temperatures up to 150 degrees. The surface is almost impossible to burn under domestic conditions. Despite its thermal stability, quartz is susceptible to thermal shock, an extreme localization of high temperature. Thermal shock can lead to cracks and chips. It is recommended to use a stand for objects removed directly from a hot stove.

Quartz stone cost

There are 11 main brands of quartz stone on the Russian market.

The material is produced in slabs ranging in size from 3000*1400 mm to 3320*1650 mm.

Size is of great importance if the designed product does not fit into the calculation unit. A shortage of just a few centimeters of material may require the purchase of an additional unit of stone, which will significantly increase the cost of the final product.

Each stone supplier has a warehouse program supported in warehouses in Moscow. On average, the warehouse program includes about 30 stone articles. Stone from a warehouse in Moscow is sold not by square meters, but by units of account. The unit of account is equal to half a slab of stone.

Custom items that are not included in the Russian warehouse program and must be delivered directly from the manufacturer’s plant are sold only in whole slabs.

It is more correct to compare the cost of stone from different manufacturers in square meters, since the size of the slabs may vary.

Quartz Manufacturers

Manufacturer country

Price per m2 (thickness 20 mm)