Moldavite, a natural glass formed by meteorite impact, from Besednice, Bohemia

A modern greenhouse in Wisley Garden, England, made from float glass

Clear glass light bulb

Glass in the common sense refers to a hard, brittle, transparent solid, such as used for windows, many bottles, or eyewear, including soda-lime glass, acrylic glass, sugar glass, isinglass (Muscovy-glass), or aluminium oxynitride. Look up Glass, glass in Wiktionary, the free dictionary. ... Image File history File links Download high resolution version (1024x717, 85 KB) Description: Moldavite from Besednice, Bohemia, Czech Republic. ... Image File history File links Download high resolution version (1024x717, 85 KB) Description: Moldavite from Besednice, Bohemia, Czech Republic. ... Moldavite from Besednice, Bohemia Moldavite is an olive-green or dull greenish vitreous substance formed by a meteorite impact. ... Willamette Meteorite A meteorite is a natural object originating in outer space that survives an impact with the Earths surface without being destroyed. ... ÄŒeský Krumlov District (Czech: ) is a district (okres) within South Bohemian Region of the Czech Republic. ... Flag of Bohemia Bohemia (Czech: ; German: ) is a historical region in central Europe, occupying the western and middle thirds of the Czech Republic. ... Image File history File links Metadata Size of this preview: 800 × 600 pixelsFull resolution (2848 × 2136 pixel, file size: 1. ... Image File history File links Metadata Size of this preview: 800 × 600 pixelsFull resolution (2848 × 2136 pixel, file size: 1. ... The Royal Greenhouses of Laeken. ... The Royal Horticultural Societys garden at Wisley in the English county of Surrey south of London, is one of the three most visited paid gardens in the United Kingdom alongside Kew Gardens and Alnwick Garden. ... For other uses, see England (disambiguation). ... Float glass is made by melting raw materilas consisting of sand, limestone, soda ash, dolomite, iron oxide and salt cake. ... Image File history File links Download high resolution version (768x1276, 92 KB) Description: en: de: Glühlampe der Marke Neolux mit klarem Glaskolben. ... Image File history File links Download high resolution version (768x1276, 92 KB) Description: en: de: Glühlampe der Marke Neolux mit klarem Glaskolben. ... For devices such as table lamps and reading lamps, see Light fixture. ... Hard: see hardness. ... A material is brittle if it is subject to fracture when subjected to stress i. ... Transparent glass ball In optics, transparency is the property of allowing light to pass. ... This box:      For other uses, see Solid (disambiguation). ... For other uses, see Window (disambiguation). ... A pair of modern glasses A pair of more traditional glasses Glasses, spectacles, or eyeglasses are frames bearing lenses worn below the forehead and in front of the human eyes, sometimes for purely aesthetic reasons but normally for vision correction or eye protection. ... Soda-lime glass is the kind of glass which is most widely used for various purposes. ... Perspex redirects here. ... Sugar glass is not glass at all, but a mixure of sugar, corn syrup and water, which looks like glass when finished. ... This article is about the mineral. ... Aluminium oxynitride (AlON) is a transparent ceramic composed of aluminium, oxygen and nitrogen. ...

In the technical sense, glass is an inorganic product of fusion which has been cooled to a rigid condition without crystallizing.^{[1][2][3][4][5]} Most glasses contain silica as their main component and glass former.^[6] The chemical compound silicon dioxide, also known as silica, is the oxide of silicon, chemical formula SiO2. ...

In the scientific sense the term glass is often extended to all amorphous solids (and melts that easily form amorphous solids), including plastics, resins, or other silica-free amorphous solids. In addition, besides traditional melting techniques, any other means of preparation are considered, such as ion implantation, and the sol-gel method.^[6] However, glass science commonly includes only inorganic amorphous solids, while plastics and similar organics are covered by polymer science, biology and further scientific disciplines. Wax and paraffin are amorphous. ... For other uses, see Plastic (disambiguation). ... This article does not cite any references or sources. ... Ion implantation is a materials engineering process by which ions of a material can be implanted into another solid, thereby changing the physical properties of the solid. ... Sol gel is a colloidal suspension of silicon dioxide that is gelled to form a solid. ... Inorganic chemistry is the branch of chemistry concerned with the properties and reactions of inorganic compounds. ... Polymer chemistry or macromolecular chemistry is a multidisciplinary science that deals with the chemical synthesis and chemical properties of polymers or macromolecules. ... For the song by Girls Aloud see Biology (song) Biology studies the variety of life (clockwise from top-left) E. coli, tree fern, gazelle, Goliath beetle Biology (from Greek: βίος, bio, life; and λόγος, logos, speech lit. ...

The optical and physical properties of glass make it suitable for applications such as flat glass, container glass, optics and optoelectronics material, laboratory equipment, thermal insulator (glass wool), reinforcement fiber (glass-reinforced plastic, glass fiber reinforced concrete), and art. For the book by Sir Isaac Newton, see Opticks. ... Optoelectronics is the study and application of electronic devices that interact with light, and thus is usually considered a sub-field of photonics. ... Laboratory equipment refers to the various tools and equipment used by scientists working in a laboratory. ... Glass wool is similar to steel wool. ... It has been suggested that Fiber-reinforced plastic be merged into this article or section. ... Glass ball made By Tyler Hopkins. ...

General properties, uses, occurrence

Laboratory glassware made from borosilicate glass (Erlenmeyer flask)

Flat panel display, using thin sheets of special alkali-free^[7] glass

Ordinary glass is prevalent due to its transparency to visible light. This transparency is due to an absence of electronic transition states in the range of visible light. The homogeneity of the glass on length scales greater than the wavelength of visible light also contributes to its transparency as heterogeneities would cause light to be scattered, breaking up any coherent image transmission. Many household objects are made of glass. Drinking glasses, bowls and bottles are often made of glass, as are light bulbs, mirrors, aquaria, cathode ray tubes, computer flat panel displays, and windows. Brown glass jars with some clear lab glassware in the background Laboratory glassware refers to a variety of equipment, traditionally made of glass, used for scientific experiments and other work in science, especially in chemistry and biology laboratories. ... It has been suggested that Kimax be merged into this article or section. ... Conical flask For the episode of The X-Files, see The Erlenmeyer Flask. ... Image File history File linksMetadata 502px-TFT_Monitor_Flachbildschirm. ... Image File history File linksMetadata 502px-TFT_Monitor_Flachbildschirm. ... Flat panel displays encompass a growing number of technologies enabling video displays that are lighter and much thinner than traditional television and video displays using cathode ray tubes, usually less than 10 cm (4 inches) thick. ... Alkaline redirects here. ... The optical spectrum (light or visible spectrum) is the portion of the electromagnetic spectrum that is visible to the human eye. ... The transition state of a chemical reaction is a particular configuration along the reaction coordinate. ... For other uses, see Wavelength (disambiguation). ... Scattering is a general physical process whereby some forms of radiation, such as light, sound or moving particles, for example, are forced to deviate from a straight trajectory by one or more localized non-uniformities in the medium through which it passes. ... Glass stemware Wikimedia Commons has media related to: Drinkware Drinkware or Beverageware is a general term for the class of vessels from which people drink. ... A salad in a bowl sits next to a small pie in a pie dish Chawan, drinking bowls used in a Japanese tea ceremony Bowls used as construction tools in contemporary India. ... The light bulb is one of the most significant inventions in the history of the human race, illuminating the darkness of the evening and bringing light indoors at all times in order focus on the task at hand. ... A mirror, reflecting a vase. ... “Aquaria” redirects here. ... The cathode ray tube or CRT, invented by Karl Ferdinand Braun, is the display device used in most computer displays, televisions and oscilloscopes. ... Flat panel displays encompass a growing number of technologies enabling video displays that are lighter and much thinner than traditional television and video displays using cathode ray tubes, usually less than 10 cm (4 inches) thick. ... For other uses, see Window (disambiguation). ...

In research laboratories, flasks, test tubes, and other laboratory equipment are often made of borosilicate glass for its low coefficient of thermal expansion, giving greater resistance to thermal shock and greater accuracy in measurements. For high-temperature applications, quartz glass is used, although it is very difficult to work. Most laboratory glassware is mass-produced, but large laboratories also keep a glassblower on staff for preparing custom made glass equipment. This article does not cite any references or sources. ... Erlenmeyer flasks from the Argonne National Laboratory glassblowing shop. ... A test tube (Sometimes culture tube) is a kind of laboratory glassware, composed of a fingerlike length of glass tubing, open at the top, sometimes with a rounded lip at the top, and a rounded U shaped bottom. ... Brown glass jars with some clear lab glassware in the background Laboratory glassware refers to a variety of equipment, traditionally made of glass, used for scientific experiments and other work in science, especially in chemistry and biology laboratories. ... It has been suggested that Kimax be merged into this article or section. ... During heat transfer, the energy that is stored in the intermolecular bonds between atoms changes. ... Thermal shock and thermal loading refer to the disfuntion (and perhaps, crack) of a material due to the heating, especially non-stationary and non-uniform. ... A sphere manufactured by NASA out of fused quartz for use in a gyroscope in the Gravity Probe B experiment. ... Brown glass jars with some clear lab glassware in the background Laboratory glassware refers to a variety of equipment, traditionally made of glass, used for scientific experiments and other work in science, especially in chemistry and biology laboratories. ... Mass production (also called flow production, repetitive flow production or series production) is the production of large amounts of standardized products on production lines. ... Glassblowing is the process of forming glass into useful shapes while the glass is in a molten, semi-liquid state. ...

Sometimes, glass is created naturally from volcanic lava, lightning strikes, or meteorite impacts (e.g., Lechatelierite, Fulgurite, Darwin Glass, Volcanic Glass). If the lava is felsic this glass is called obsidian, and is usually black with impurities. Obsidian is a raw material for flintknappers, who have used it to make extremely sharp glass knives since the stone age. Look up lava, Aa, pahoehoe in Wiktionary, the free dictionary. ... Not to be confused with lighting. ... Willamette Meteorite A meteorite is a natural object originating in outer space that survives an impact with the Earths surface without being destroyed. ... Lechatelierite is silica glass, amorphous SiO2. ... fulgurite Fulgurites (from the Latin fulgur meaning thunderbolt) are natural hollow carrot-shaped glass tubes formed in quartzose sand or soil by lightning strikes. ... Darwin Glass is a natural glass found to the east of Mount Darwin in the area known as the Darwin Meteorite impact crater in West Coast Tasmania just east of the West Coast Range. ... Top stone is obsidian, below that is pumice and in lower right hand is rhyolite (light color) Obsidian is a type of naturally occurring glass, produced from volcanoes when the right kind of lava cools rapidly, e. ... Felsic is a term used in geology to refer to silicate minerals, magmas, and rocks which are enriched in the lighter elements such as silica, oxygen, aluminium, sodium, and potassium. ... This article is about a type of volcanic glass. ... A flintknapper is an individual who shapes flint or other stone through the process of knapping or lithic reduction no shit sherlock, to manufacture stone tools, strikers for flintlock firearms, or to produce flat-faced stones for building or facing walls. ... In electron microscopy, glass knives are used to make the ultrathin sections needed for imaging. ... Stone Age fishing hook. ...

Glass sometimes occurs in nature resulting from human activity, for example trinitite (from nuclear testing) and beach glass. Sample of Trinitite. ...

Glass in buildings

Main articles: Architectural Glass, Glazing in architecture, and Window

Extensive use of float glass sheets in apartments in Bristol, England.

Glass is commonly used in buildings as transparent windows, internal glazed partitions, and as architectural features. It is also possible to use glass as a structural material, for example, in beams and columns, as well as in the form of "fins" for wind reinforcement, which are visible in many glass frontages like large shop windows. Safe load capacity is, however, limited; although glass has a high theoretical yield stress, it is very susceptible to brittle (sudden) failure, and has a tendency to shatter upon localized impact. This particularly limits its use in columns, as there is a risk of vehicles or other heavy objects colliding with and shattering the structural element. One well-known example of a structure made entirely from glass is the northern entrance to Buchanan Street subway station in Glasgow. Architectural glass has been used in buildings since the 11th century. ... Glazing, in architecture, is a transparent part of a wall, usually made of glass or plastic (acrylic and polycarbonate). ... For other uses, see Window (disambiguation). ... Float glass is made by melting raw materilas consisting of sand, limestone, soda ash, dolomite, iron oxide and salt cake. ... This article is about the English city. ... For other uses, see England (disambiguation). ... Buchanan Street subway station is a station on the Glasgow Subway in Glasgow, Scotland. ... For other uses, see Glasgow (disambiguation). ...

Glass in buildings can be of a safety type, including wired, heat strengthened (tempered) and laminated glass. Glass fibre insulation is common in roofs and walls. Foamed glass, made from waste glass, can be used as lightweight, closed-cell insulation. As insulation, glass (e.g., fiberglass) is also used. In the form of long, fluffy-looking sheets, it is commonly found in homes. Fiberglass insulation is used particularly in attics, and is given an R-rating, denoting the insulating ability. Bundle of fiberglass Fiberglass (also called fibreglass and glass fibre) is material made from extremely fine fibers of glass. ...

Technological applications

Uses of glass for scientific purposes range from applications such as DNA microarrays to large sized neodymium doped glass lasers and glass fibres

The Hubble Space Telescope orbiting above earth, containing optical instruments

Pure SiO₂ glass (the same chemical compound as quartz, or, in its polycrystalline form, sand) does not absorb UV light and is used for applications that require transparency in this region. Large natural single crystals of quartz are pure silicon dioxide, and upon crushing are used for high quality specialty glasses. Synthetic amorphous silica, an almost 100 % pure form of quartz, is the raw material for the most expensive specialty glasses, such as optical fiber core. Undersea cables have sections doped with erbium, which amplify transmitted signals by laser emission from within the glass itself. Amorphous SiO₂ is also used as a dielectric material in integrated circuits due to the smooth and electrically neutral interface it forms with silicon. It has been suggested that Gene chip technology be merged into this article or section. ... General Name, Symbol, Number neodymium, Nd, 60 Chemical series lanthanides Group, Period, Block n/a, 6, f Appearance silvery white, yellowish tinge Standard atomic weight 144. ... For alternative meanings see laser (disambiguation). ... Image File history File links Download high resolution version (945x766, 76 KB) Hubble Space Telescope as seen from the Space Shuttle Discovery on mission STS-82. ... Image File history File links Download high resolution version (945x766, 76 KB) Hubble Space Telescope as seen from the Space Shuttle Discovery on mission STS-82. ... The Hubble Space Telescope (HST) is a telescope in orbit around the Earth, named after astronomer Edwin Hubble. ... ... A sphere manufactured by NASA out of fused quartz for use in a gyroscope in the Gravity Probe B experiment. ... For other uses, see Quartz (disambiguation). ... ]]s are polycrystalline. ... For other uses, see Sand (disambiguation). ... Note: Ultraviolet is also the name of a 1998 UK television miniseries about vampires. ... For other uses, see Light (disambiguation). ... Optical fibers An optical fiber (or fibre) is a glass or plastic fiber designed to guide light along its length. ... The multitude of layers in a submarine communications cable is revealed by its Cross section. ... General Name, Symbol, Number erbium, Er, 68 Chemical series lanthanides Group, Period, Block n/a, 6, f Appearance silvery white Standard atomic weight 167. ... In telecommunication, an optical amplifier is a device that amplifies an optical signal directly, without the need to convert it to an electrical signal, or amplify it electrically, and reconvert it to an optical signal. ... For other uses, see Laser (disambiguation). ... A dielectric is a nonconducting substance, i. ... Integrated circuit of Atmel Diopsis 740 System on Chip showing memory blocks, logic and input/output pads around the periphery Microchips with a transparent window, showing the integrated circuit inside. ... Not to be confused with Silicone. ...

Optical instruments such as glasses, cameras, microscopes, telescopes, and planetaria are based on glass lenses, mirrors, and prisms. The glasses used for making these instruments are categorized using a six-digit glass code, or alternatively a letter-number code from the Schott Glass catalogue. For example, BK7 is a low-dispersion borosilicate crown glass, and SF10 is a high-dispersion dense flint glass. The glasses are arranged by composition, refractive index, and Abbe number. ... A pair of modern glasses Glasses, also called eyeglasses or spectacles are frames, bearing lenses worn in front of the eyes normally for vision correction, eye protection, or for protection from UV rays. ... For other uses, see Camera (disambiguation). ... An 1879 Carl Zeiss Jena Optical microscope. ... Eight Inch refracting telescope. ... For the song by Ai Otsuka, see Planetarium (song) // A planetarium is a theatre built primarily for presenting educational and entertaining shows about astronomy and the night sky, or for training in celestial navigation. ... This article is about the optical device. ... A mirror, reflecting a vase. ... If a shaft of light entering a prism is sufficiently narrow, a spectrum results. ... A glass code is a method of classifying glasses for optical use, such as the manufacture of lenses and prisms. ... Schott Glass AG is a manufacturer of high-quality industrial glass products, such as fiber-optics and components used in flat panel displays. ... Dispersion of a light beam in a prism. ... It has been suggested that Kimax be merged into this article or section. ... Crown glass is a type of optical glass used in lenses. ... Flint glass is an optical glass that has relatively high refractive index and low Abbe number. ... In physics and optics, the Abbe number, also known as the V-number or constringence of a transparent material is a measure of the materials dispersion (variation of refractive index with wavelength). ...

Glass polymerization is a technique that can be used to incorporate additives that modify the properties of glass that would otherwise be destroyed during high temperature preparation. Sol gel is an example of glass polymerization and enables embedding of organic and bioactive molecules, to add a new level of functionality to glass.^[8] An example of alkene polymerisation, in which each Styrene monomer units double bond reforms as a single bond with another styrene monomer and forms polystyrene. ... Sol gel is an inorganic, catalytic silicon oxide gel, used for its negative tone photosensitive properties. ...

Glass production

Main articles: Glass production and Float glass

Float glass is made by melting raw materilas consisting of sand, limestone, soda ash, dolomite, iron oxide and salt cake. ...

Glass production history

Glass melting technology has passed through several stages:^[9]

• Glass was manufactured in open pits, ca. 3000 B.C. until the invention of the blowpipe in ca. 250 B.C.

• The mobile wood-fired melting pot furnace was used until around the 17th century by traveling glass manufacturers.

• Around 1688, a process for casting glass was developed, which led to glass becoming a much more commonly used material.^{[citation needed]}

• The local pot furnace, fired by wood and coal was used between 1600 and 1850.

• The cylinder method of creating flat glass was used in the United States of America for the first time in the 1820s. It was used to commercially produce windows.^{[citation needed]}

• The invention of the glass pressing machine in 1827 allowed the mass production of inexpensive glass products.^{[citation needed]}

• The gas-heated melting pot and tank furnaces dating from 1860, followed by the electric furnace of 1910.

• Hand-blown sheet glass was replaced in the 20th century by rolled plate glass.^{[citation needed]}

• The float glass process was invented in the 1950s.

This article is about the manufacturing process. ... Cylinder blown sheet is a type of hand-blown window glass. ... Motto: (traditional) In God We Trust (official, 1956–present) Anthem: The Star-Spangled Banner Capital Washington, D.C. Largest city New York City Official language(s) None at the federal level; English de facto Government Federal Republic  - President George W. Bush (R)  - Vice President Dick Cheney (R) Independence - Declared - Recognized... Float glass is made by melting raw materilas consisting of sand, limestone, soda ash, dolomite, iron oxide and salt cake. ...

Glass ingredients

Quartz sand (silica) as main raw material for commercial glass production

Pure silica (SiO₂) has a "glass melting point"— at a viscosity of 10 Pa·s (100 P)— of over 2300 °C (4200 °F). While pure silica can be made into glass for special applications (see fused quartz), other substances are added to common glass to simplify processing. One is sodium carbonate (Na₂CO₃), which lowers the melting point to about 1500 °C (2700 °F) in soda-lime glass; "soda" refers to the original source of sodium carbonate in the soda ash obtained from certain plants. However, the soda makes the glass water soluble, which is usually undesirable, so lime (calcium oxide (CaO), generally obtained from limestone), some magnesium oxide (MgO) and aluminium oxide are added to provide for a better chemical durability. The resulting glass contains about 70 to 74 percent silica by weight and is called a soda-lime glass.^[9] Soda-lime glasses account for about 90 percent of manufactured glass. For other uses, see Sand (disambiguation). ... The chemical compound silicon dioxide, also known as silica, is the oxide of silicon, chemical formula SiO2. ... For other uses, see Viscosity (disambiguation). ... The pascal second (symbol Pa·s) is the SI unit of dynamic viscosity. ... The poise (P; IPA: ) is the unit of dynamic viscosity in the centimetre gram second system of units. ... For other uses, see Celsius (disambiguation). ... For other uses, see Fahrenheit (disambiguation). ... A sphere manufactured by NASA out of fused quartz for use in a gyroscope in the Gravity Probe B experiment. ... Sodium carbonate (also known as washing soda or soda ash), Na2CO3, is a sodium salt of carbonic acid. ... Soda-lime glass is the kind of glass which is most widely used for various purposes. ... Look up soda in Wiktionary, the free dictionary. ... Sodium carbonate or soda ash, Na2CO3, is a sodium salt of carbonic acid. ... This article or section does not adequately cite its references or sources. ... Calcium oxide (CaO), commonly known as lime, quicklime or burnt lime, is a widely used chemical compound. ... For other uses, see Limestone (disambiguation). ... Soda-lime glass is the kind of glass which is most widely used for various purposes. ...

As well as soda and lime, most common glass has other ingredients added to change its properties. Lead glass, such as lead crystal or flint glass, is more 'brilliant' because the increased refractive index causes noticeably more "sparkles", while boron may be added to change the thermal and electrical properties, as in Pyrex. Adding barium also increases the refractive index. Thorium oxide gives glass a high refractive index and low dispersion, and was formerly used in producing high-quality lenses, but due to its radioactivity has been replaced by lanthanum oxide in modern glasses. Large amounts of iron are used in glass that absorbs infrared energy, such as heat absorbing filters for movie projectors, while cerium(IV) oxide can be used for glass that absorbs UV wavelengths (biologically damaging ionizing radiation). General Name, Symbol, Number lead, Pb, 82 Chemical series Post-transition metals or poor metals Group, Period, Block 14, 6, p Appearance bluish gray Standard atomic weight 207. ... Lead crystal beads Lead crystal, (also called crystal), is lead glass that has been hand or machine cut with facets. ... Flint glass is an optical glass that has relatively high refractive index and low Abbe number. ... The refractive index (or index of refraction) of a medium is a measure for how much the speed of light (or other waves such as sound waves) is reduced inside the medium. ... For other uses, see Boron (disambiguation). ... // For the programming language, see Pyrex (programming language). ... For other uses, see Barium (disambiguation). ... Thorium dioxide (ThO2), also called thorium(IV) oxide (IUPAC) is a white, crystalline powder. ... Radioactivity may mean: Look up radioactivity in Wiktionary, the free dictionary. ... Lanthanum(III) oxide is a white solid. ... General Name, symbol, number iron, Fe, 26 Chemical series transition metals Group, period, block 8, 4, d Appearance lustrous metallic with a grayish tinge Standard atomic weight 55. ... For other uses, see Infrared (disambiguation). ... Cerium(IV) oxide, ceric oxide, ceria, or sometimes simply cerium oxide or cerium dioxide, is a pale yellow-white powder, CeO2. ... Note: Ultraviolet is also the name of a 1998 UK television miniseries about vampires. ...

Besides the chemicals mentioned, in some furnaces recycled glass ("cullet") is added, originating from the same factory or other sources. Cullet leads to savings not only in the raw materials, but also in the energy consumption of the glass furnace. However, impurities in the cullet may lead to product and equipment failure. Fining agents such as sodium sulfate, sodium chloride, or antimony oxide are added to reduce the bubble content in the glass.^[9] Sodium sulfate is an important compound of sodium. ... R-phrases 36 S-phrases none Flash point Non-flammable Related Compounds Other anions NaF, NaBr, NaI Other cations LiCl, KCl, RbCl, CsCl, MgCl2, CaCl2 Related salts Sodium acetate Supplementary data page Structure and properties n, εr, etc. ... Antimony trioxide is the most important commercial compound of antimony. ...

A further raw material used in the production of soda-lime and fiber glass is calumite, which is a glassy granular by-product of the iron making industry, containing mainly silica, calcium oxide, alumina, magnesium oxide (and traces of iron oxide).^[10]

For obtaining the desired glass composition, the correct raw material mixture (batch) must be determined by glass batch calculation.

Contemporary glass production

Following the glass batch preparation and mixing the raw materials are transported to the furnace. Soda-lime glass for mass production is melted in gas fired units. Smaller scale furnaces for specialty glasses include electric melters, pot furnaces and day tanks.^[9] Soda-lime glass is the kind of glass which is most widely used for various purposes. ...

After melting, homogenization and refining (removal of bubbles) the glass is formed. Flat glass for windows and similar applications is formed by the float glass process, developed between 1953 and 1957 by Sir Alastair Pilkington and Kenneth Bickerstaff of the UK's Pilkington Brothers, which created a continuous ribbon of glass using a molten tin bath on which the molten glass flows unhindered under the influence of gravity. Container glass for common bottles and jars is formed by blowing and pressing methods. Further glass forming techniques are summarized in the table Glass forming techniques. Float glass is made by melting raw materilas consisting of sand, limestone, soda ash, dolomite, iron oxide and salt cake. ... Lionel Alexander Bethune Pilkington, (7 January 1920–5 May 1995) (Sir Alastair Pilkington) and his associate Kenneth Bickerstaff developed the first commercially successful implementation of float glass even though the float glass process was patented three times before their own patent was issued. ...

Once the desired form is obtained, glass is usually annealed for the removal of stresses. Annealing, in glassblowing and lampworking, is the process of heating, and then slowly cooling glass to increase softness (ductility) and durability. ...

Various surface treatment techniques, coatings, or lamination may follow to improve the chemical durability (glass container coatings, glass container internal treatment), strength (toughened glass, bulletproof glass, windshields), or optical properties (insulated glazing, anti-reflective coating). A laminate is a material constructed by uniting two or more layers of material together. ... A vandalized telephone booth with toughened glass Toughened glass or tempered glass is a type of glass that has increased strength and will usually shatter into small fragments when broken. ... Strictly, Bulletproof glass would be glass that is capable of stopping all manner of bullets fired at it. ... Panoramic (wrap-around) windshield on a 1959 Edsel Corsair. ... Insulated Glazing Unit or Insulating Glass Unit (commonly referred to as IGU) is described as two or more lites of glass spaced apart and hermetically sealed to form a single glazed unit with an air space between each lite. ... Anti-reflective coatings are a type of optical coating applied to lenses and other devices to reduce reflection from optical surfaces. ...

Glassmaking in the laboratory

A vitrification experiment for the study of nuclear waste disposal at Pacific Northwest National Laboratory.

Failed laboratory glass melting test. The striations must be avoided through good homogenization.

New chemical glass compositions or new treatment techniques can be initially investigated in small-scale laboratory experiments. The raw materials for laboratory-scale glass melts are often different from those used in mass production because the cost factor has a low priority. In the laboratory mostly pure chemicals are used. Care must be taken that the raw materials have not reacted with moisture or other chemicals in the environment (such as alkali oxides and hydroxides, alkaline earth oxides and hydroxides, or boron oxide), or that the impurities are quantified (loss on ignition).^[11] Evaporation losses during glass melting should be considered during the selection of the raw materials, e.g., sodium selenite may be preferred over easily evaporating SeO₂. Also, more readily reacting raw materials may be preferred over relatively inert ones, such as Al(OH) ₃ over Al₂O₃. Usually, the melts are carried out in platinum crucibles to reduce contamination from the crucible material. Glass homogeneity is achieved by homogenizing the raw materials mixture (glass batch), by stirring the melt, and by crushing and re-melting the first melt. The obtained glass is usually annealed to prevent breakage during processing.^[11][12] Download high resolution version (1143x1226, 461 KB)A vitrification experiment. ... Download high resolution version (1143x1226, 461 KB)A vitrification experiment. ... Political Punk band from Victorville, Ca WWW.MYSPACE.COM/NUCLEARWASTEX ... The Pacific Northwest National Laboratory (PNNL) is a one of nine United States Department of Energy multiprogram national laboratories. ... Homogenization (or homogenisation) is a term used in many fields such as Chemistry, agricultural science, food technology, sociology and cell biology. ... This article does not cite any references or sources. ... A chemical substance is any material substance used in or obtained by a process in chemistry: A chemical compound is a substance consisting of two or more chemical elements that are chemically combined in fixed proportions. ... The alkali metals are a series of elements comprising Group 1 (IUPAC style) of the periodic table: lithium (Li), sodium (Na), potassium (K), rubidium (Rb), caesium (Cs), and francium (Fr). ... The alkaline earth metals are a series of elements comprising Group 2 (IUPAC style) of the periodic table: beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba) and radium (Ra). ... Boron oxide is a colourless or white solid, also known as Diboron trioxide, formula B2O3. ... R-phrases , , S-phrases , , , , U.S. Permissible Exposure Limit 5 ppm IDLH (NIOSH) 100 ppm Flash point non-flammable RTECS number WS4550000 Supplementary data page Structure and properties n, εr, etc. ... In English, to be inert is to be in a state of doing little or nothing. ... Aluminium hydroxide, Al(OH)3, is the most stable form of aluminium in normal conditions. ... Alumina redirects here. ... Homogenization (or homogenisation) is a term used in many fields such as Chemistry, agricultural science, food technology, sociology and cell biology. ... Annealing, in glassblowing and lampworking, is the process of heating, and then slowly cooling glass to increase softness (ductility) and durability. ...

See also: Optical lens design, Fabrication and testing of optical components Optical lens design is the science/art of calculating the various lens construction parameters (variables) that will meet or at least approach desired performance requirements while staying within required constraint values. ...

Silica-free glasses

Besides common silica-based glasses, many other inorganic and organic materials may also form glasses, including plastics (e.g., acrylic glass), carbon, metals, carbon dioxide (see below), phosphates, borates, chalcogenides, fluorides, germanates (glasses based on GeO₂), tellurites (glasses based on TeO₂), antimonates (glasses based on Sb₂O₃), arsenates (glasses based on As₂O₃), titanates (glasses based on TiO₂), tantalates (glasses based on Ta₂O₅), nitrates, carbonates and many other substances.^[6] The chemical compound silicon dioxide, also known as silica, is the oxide of silicon, chemical formula SiO2. ... Inorganic chemistry is the branch of chemistry concerned with the properties and reactions of inorganic compounds. ... Organic chemistry is a specific discipline within chemistry which involves the scientific study of the structure, properties, composition, reactions, and preparation (by synthesis or by other means) of chemical compounds consisting primarily of carbon and hydrogen, which may contain any number of other elements, including nitrogen, oxygen, the halogens as... The term plastics covers a range of synthetic or semi-synthetic organic condensation or polymerization products that can be molded or extruded into objects or films or fibers. ... Perspex redirects here. ... For other uses, see Carbon (disambiguation). ... This article or section should be merged with Amorphous metal Amorphous Metals are metals whose structure defies the typical crystalline nature of most metals and alloys. ... A phosphate, in inorganic chemistry, is a salt of phosphoric acid. ... Borates in chemistry are chemical compounds containing boron bonded to three oxygen atoms written as B(OR)3. ... A Chalcogenide glass is a glass containing a chalcogenide element (sulphur, selenium or tellurium) as a substantial constituent. ... Fluoride is the ionic form of fluorine. ... Germanium dioxide, also called germanium oxide and germania, is an inorganic compound, an oxide of germanium. ... Trinitrate redirects here. ... Ball-and-stick model of the carbonate ion, CO32− For other meanings, see Carbonate (disambiguation) In chemistry, a carbonate is a salt or ester of carbonic acid. ...

Some glasses that do not include silica as a major constituent may have physico-chemical properties useful for their application in fibre optics and other specialized technical applications. These include fluorozirconate, fluoroaluminate, aluminosilicate, phosphate and chalcogenide glasses. Fiber Optic strands An optical fiber in American English or fibre in British English is a transparent thin fiber for transmitting light. ... Aluminosilicate minerals are minerals that have the basic structure and composition of AlSiO4. ... A phosphate, in inorganic chemistry, is a salt of phosphoric acid. ... A Chalcogenide glass is a glass containing a chalcogenide element (sulphur, selenium or tellurium) as a substantial constituent. ...

Under extremes of pressure and temperature solids may exhibit large structural and physical changes which can lead to polyamorphic phase transitions.^[13] In 2006 Italian scientists created an amorphous phase of carbon dioxide using extreme pressure. The substance was named amorphous carbonia(a-CO₂) and exhibits an atomic structure resembling that of Silica.^[14] In materials science polyamorphism is the ability of a substance to exist in several different amorphous modifications. ... Carbon dioxide (chemical formula: ) is a chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom. ... Amorphous carbonia, also called a-carbonia or a-CO2, is an exotic amorphous solid form of carbon dioxide that is analogous to amorphous silica glass. ...

The physics of glass

The amorphous structure of glassy Silica (SiO₂). No long range order is present, however there is local ordering with respect to the tetrahedral arrangement of Oxygen (O) atoms around the Silicon (Si) atoms.

The standard definition of a glass (or vitreous solid) requires the solid phase to be formed by rapid melt quenching.^[2][3][4] Glass is therefore formed via a supercooled liquid and cooled sufficiently rapidly (relative to the characteristic crystallisation time) from its molten state through its glass transition temperature, T_g, that the supercooled disordered atomic configuration at T_g, is frozen into the solid state. Generally, the structure of a glass exists in a metastable state with respect to its crystalline form, although in certain circumstances, for example in atactic polymers, there is no crystalline analogue of the amorphous phase ^[15]. By definition as an amorphous solid, the atomic structure of a glass lacks any long range translational periodicity. However, by virtue of the local chemical bonding constraints glasses do possess a high degree of short-range order with respect to local atomic polyhedra^[16]. It is deemed that the bonding structure of glasses, although disordered, has the same symmetry signature (Hausdorff-Besicovitch dimensionality) as for crystalline materials^[17]. Image File history File links No higher resolution available. ... Image File history File links No higher resolution available. ... A tetrahedron (plural: tetrahedra) is a polyhedron composed of four triangular faces, three of which meet at each vertex. ... Vitreous refers to a material in an amorphous, glassy state (in contrast to a crystalline state). ... Supercooling is the process of chilling a liquid below its freezing point, without its becoming solid. ... Crystal (disambiguation) Insulin crystals A crystal is a solid in which the constituent atoms, molecules, or ions are packed in a regularly ordered, repeating pattern extending in all three spatial dimensions. ... The glass transition temperature is the temperature below which the physical properties of amorphous materials vary in a manner similar to those of a solid phase (glassy state), and above which amorphous materials behave like liquids (rubbery state). ... Metastability in molecules is the ability of a non-equilibrium chemical state to persist for a long period of time. ... Crystal (disambiguation) Insulin crystals A crystal is a solid in which the constituent atoms, molecules, or ions are packed in a regularly ordered, repeating pattern extending in all three spatial dimensions. ... In atactic macromolecules every substituent belonging to a repeating unit is placed randomly at either side of the backbone. ... Wax and paraffin are amorphous. ... In geometry, a translation slides an object by a vector a: Ta(p) = p + a. ... In chemistry, a chemical bond is the force which holds together atoms in molecules or crystals. ... In mathematics, there are three related meanings of the term polyhedron: in the traditional meaning it is a 3-dimensional polytope, and in a newer meaning that exists alongside the older one it is a bounded or unbounded generalization of a polytope of any dimension. ... In mathematics, the Hausdorff dimension is an extended non-negative real number associated to any metric space. ...

Glass versus a supercooled liquid

Glass is generally treated as an amorphous solid rather than a liquid, though both views can be justified.^[18] However, the notion that glass flows to an appreciable extent over extended periods of time is not supported by empirical research or theoretical analysis (see viscosity of amorphous materials). From a more commonsense point of view, glass should be considered a solid since it is rigid according to everyday experience.^[19] Wax and paraffin are amorphous. ... Viscosity of amorphous materials: Viscous flow in amorphous materials (e. ...

Some people believe glass is a liquid due to its lack of a first-order phase transition ^[18][20] where certain thermodynamic variables such as volume, entropy and enthalpy are continuous through the glass transition temperature. However, the glass transition temperature may be described as analogous to a second-order phase transition where the intensive thermodynamic variables such as the thermal expansivity and heat capacity are discontinuous. Despite this, thermodynamic phase transition theory does not entirely hold for glass, and hence the glass transition cannot be classed as a genuine thermodynamic phase transition.^[4] This diagram shows the nomenclature for the different phase transitions. ... Thermodynamics (from the Greek θερμη, therme, meaning heat and δυναμις, dynamis, meaning power) is a branch of physics that studies the effects of changes in temperature, pressure, and volume on physical systems at the macroscopic scale by analyzing the collective motion of their particles using statistics. ... In thermodynamics, state variables, state parameters or thermodynamic variables describe the momentary condition of a system. ... For other uses, see Volume (disambiguation). ... For other uses, see: information entropy (in information theory) and entropy (disambiguation). ... t In thermodynamics and molecular chemistry, the enthalpy or heat content (denoted as H or ΔH, or rarely as χ) is a quotient or description of thermodynamic potential of a system, which can be used to calculate the useful work obtainable from a closed thermodynamic system under constant pressure. ... In physics, thermal expansion is the tendency of matter to change in volume in response to a change in temperature. ... To meet Wikipedias quality standards, this article or section may require cleanup. ...

Although the atomic structure of glass shares characteristics of the structure in a supercooled liquid, glass is generally classed as solid below its glass transition temperature.^[21] There is also the problem that a supercooled liquid is still a liquid and not a solid but it is below the freezing point of the material and will crystallize almost instantly if a crystal is added as a core. The change in heat capacity at a glass transition and a melting transition of comparable materials are typically of the same order of magnitude indicating that the change in active degrees of freedom is comparable as well. Both in a glass and in a crystal it is mostly only the vibrational degrees of freedom that remain active, whereas rotational and translational motion becomes impossible explaining why glasses and crystalline materials are hard. For other uses, see Atom (disambiguation)