Glass generally refers to hard Hardness refers to various properties of matter in the solid phase that give it high resistance to various kinds of shape change when force is applied. Hard matter is contrasted with soft matter, brittle A material is brittle if it is liable to fracture when subjected to stress. That is, it has little tendency to deform before fracture. This fracture absorbs relatively little energy, even in materials of high strength, and usually makes a snapping sound, transparent material In the field of optics, transparency is the material property of allowing light to pass through a substance. The opposite property is opacity. Transparent materials are clear . Translucent materials allow light to pass through them only diffusely (i.e. they cannot be seen through clearly), such as those used for windows A window is a transparent opening in a wall that allows the passage of light and, if not closed or sealed, air and sound. Windows are usually glazed or covered in some other transparent or translucent material. Windows are held in place by frames, which prevent them from collapsing in, many bottles Glass bottles are bottles created from glass. They can vary in size considerably, but are most commonly found in sizes ranging between about 10ml and 5 litres, or eyewear Glasses or specs, more formally known as 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. Examples of such materials include, but are not limited to, soda-lime glass Soda-lime glass, also called soda-lime-silica glass, is the most prevalent type of glass, used for windowpanes, and glass containers for beverages, food, and some commodity items. Glass bakeware is often made of tempered soda-lime glass, borosilicate glass Borosilicate glass is a type of glass with the main glass-forming constituents silica and boron oxide. Borosilicate glasses are most well known for having very low coefficient of thermal expansion , making them resistant to thermal shock, more so than any other common glass, acrylic glass Poly (PMMA) poly(methyl 2-methylpropenoate) is a thermoplastic and transparent plastic. Chemically, it is the synthetic polymer of methyl methacrylate. It is sold under many trade names, including Policril, Plexiglas, Gavrieli, Vitroflex, Limacryl, R-Cast, Per-Clax, Perspex, Plazcryl, Acrylex, Acrylite, Acrylplast, Altuglas, Polycast, Oroglass,, sugar glass Sugar glass is an edible mixture of sugar, corn syrup and water, which has the appearance of glass when hardened for a limited time before warping and melting. It is used in stunt sequences of television and film in the place of real glass, as it breaks more easily and is less dangerous than real glass. Sugar glass must be used soon after, isinglass Muscovite is a phyllosilicate mineral of aluminium and potassium with formula K (Muscovy-glass), or aluminium oxynitride Aluminium oxynitride is a transparent ceramic composed of aluminium, oxygen and nitrogen. It is marketed under the name ALON and described in U.S. Patent 4,520,116. The material remains solid up to 1,200 °C (2,190 °F), and is harder than glass. When formed and polished as a window, the material currently (2005) costs about US$10 to US$15 per. In the technical sense, glass is an inorganic product of fusion which has been cooled through the glass transition Glass transition or vitrification refer to the transformation of a glass-forming liquid into a glass, which usually occurs upon rapid cooling. It is a dynamic phenomenon occurring between two distinct states of matter , each with different physical properties. Upon cooling through the temperature range of glass transition (a "glass to a rigid condition without crystallizing.[1][2][3][4][5] Many glasses contain silica The chemical compound silicon dioxide, also known as silica , is an oxide of silicon with a chemical formula of Si as their main component and glass former.[6]

In the scientific sense the term glass is often extended to all amorphous solids An "amorphous solid" is a solid in which there is no long-range order of the positions of the atoms. . Most classes of solid materials can be found or prepared in an amorphous form. For instance, common window glass is an amorphous solid, many polymers (such as polystyrene) are amorphous, and even foods such as cotton candy are amorphous (and melts Melt is the term used to describe the working material in the steelmaking process, in making glass, and when forming thermoplastics. For thermoplastics, the term specifically refers to the plastic in its forming temperature, which can vary depending on how it is being used. For steelmaking, it refers to steel in liquid form that easily form amorphous solids), including plastics Plastic is the general common term for a wide range of synthetic or semisynthetic organic amorphous solid materials suitable for the manufacture of industrial products. Plastics are typically polymers of high molecular weight, and may contain other substances to improve performance and/or reduce costs, resins Resin is a hydrocarbon secretion of many plants, particularly coniferous trees. It is valued for its chemical constituents and uses, such as varnishes and adhesives, as an important source of raw materials for organic synthesis, or for incense and perfume. Fossilized resins are the source of amber. Resins are also a material in nail polish, or other silica-free amorphous solids. In addition, besides traditional melting Glass production comprehends two types of glass: sheet glass, made by the float glass process, and (ii) glass-container glass techniques, any other means of preparation are considered, such as ion implantation 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. Ion implantation is used in semiconductor device fabrication and in metal finishing, as well as various applications in materials science research. The ions introduce both a, and the sol-gel The sol-gel process is a wet-chemical technique widely used recently in the fields of materials science and ceramic engineering. Such methods are used primarily for the fabrication of materials (typically a metal oxide) starting from a chemical solution which acts as the precursor for an integrated network (or gel) of either discrete particles or method.[6] However, and physics The physics of glass is the science of the glassy or amorphous state of matter as seen from an atomic or molecular point of view. This article provides an overview of research into glass: a solid in which no significant crystallization has occurred. Thus there is no long-range ordering or extended formation of any Bravais lattice commonly includes only inorganic Traditionally, inorganic compounds are considered to be of a mineral, not biological, origin. Complementarily, most organic compounds are traditionally viewed as being of biological origin. Over the past century, the precise classification of inorganic vs organic compounds has become less important to scientists, primarily because the majority of amorphous solids, while plastics and similar organics are covered by polymer science Polymer science or macromolecular science is the subfield of materials science concerned with polymers, primarily synthetic polymers such as plastics. The field of polymer science includes researchers in multiple disciplines including chemistry, physics, and engineering, biology Biology is the science that studies living organisms. Prior to the nineteenth century, biology came under the general study of all natural objects called natural history. The term biology was first coined by Gottfried Reinhold Treviranus.[citation needed] It is now a standard subject of instruction at schools and universities around the world, and and further scientific disciplines.

Glass plays an essential role in science and industry. The optical and physical properties of glass make it suitable for applications such as flat glass Flat glass, sheet glass, or plate glass is a type of glass, initially produced in plane form, commonly used for windows, glass doors, transparent walls, and windshields. For modern architectural and automotive applications, the flat glass is sometimes bent after production of the plane sheet. Flat glass stands in contrast to container glass and, container glass Container glass is a type of glass for the production of glass containers, such as bottles, jars, drinkware, and bowls. Container glass stands in contrast to flat glass and fiberglass (used for thermal insulation and optical communication). Most container glass is soda-lime glass, produced by blowing and pressing techniques, while some laboratory, optics Optics is the study of the behavior and properties of light, including its interactions with matter and the construction of instruments that use or detect it. Optics usually describes the behavior of visible, ultraviolet, and infrared light. Because light is an electromagnetic wave, other forms of electromagnetic radiation such as X-rays, and optoelectronics Optoelectronics is the study and application of electronic devices that source, detect and control light, usually considered a sub-field of photonics. In this context, light often includes invisible forms of radiation such as gamma rays, X-rays, ultraviolet and infrared, in addition to visible light. Optoelectronic devices are electrical-to- material, laboratory equipment Laboratory equipment refers to the various tools and equipment used by scientists working in a laboratory. These include tools such as Bunsen burners, and microscopes as well as specialty equipment such as operant conditioning chambers, spectrophotometers and calorimeters. Another important type of laboratory equipment is Laboratory glassware, thermal insulator (glass wool Glass wool is an insulating material, made from very thin strands of glass are arranged into a texture similar to wool. Glass wool is produced in rolls or in slabs, with different thermal and mechanical properties), reinforcement fiber (glass-reinforced plastic Glass-reinforced plastic is a composite material or fiber-reinforced plastic made of a plastic reinforced by fine fibers made of glass. Like carbon fiber reinforced plastic, the composite material is commonly referred to by the name of its reinforcing fibers . The plastic is thermosetting, most often polyester or vinylester, but other plastics,, glass fiber reinforced concrete Glass Fiber Reinforced Concrete is a type of fiber reinforced concrete. Glass fiber concretes are mainly used in exterior building façade panels and as architectural precast concrete. This material is very good in making shapes on the front of any building and it is less dense than steel), and art Glass art and glass sculpture is the use of glass as an artistic medium to produce sculptures or two-dimensional artworks. Specific approaches include stained glass, working glass in a torch flame , glass beadmaking, glass casting, glass fusing, and, most notably, glass blowing. As a decorative and functional medium, glass was extensively.

The term glass developed in the late Roman Empire The Roman Empire was the post-Republican phase of the ancient Roman civilization, characterised by an autocratic form of government and large territorial holdings in Europe and around the Mediterranean. The term is used to describe the Roman state during and after the time of the first emperor, Augustus. The nearly 500-year-old Roman Republic,. It was in the Roman glassmaking Roman glass objects have been recovered across the Roman Empire in domestic, industrial and funerary contexts. Glass was used primarily for the production of vessels, although mosaic tiles and window glass were also produced. Roman glass production developed from Hellenistic technical traditions, initially concentrating on the production of center at Trier Trier is a city in Germany on the banks of the Moselle River. It is the oldest city in Germany, founded in or before 16 BC. Trier is not the only city claiming to be Germany's oldest, but it is the only one that bases this assertion on having the longest history as a city, as opposed to a mere settlement or army camp.[citation needed], Germany Germany (pronounced /ˈdʒɜrməni/ ), officially the Federal Republic of Germany (German: Bundesrepublik Deutschland, pronounced [ˈbʊndəsʁepuˌbliːk ˈdɔʏtʃlant] ( listen)), is a country in Central Europe. It is bordered to the north by the North Sea, Denmark, and the Baltic Sea; to the east by Poland and the Czech Republic; to the south, that the late-Latin term glesum originated, probably from a Germanic word for a transparent In the field of optics, transparency is the material property of allowing light to pass through a substance. The opposite property is opacity. Transparent materials are clear . Translucent materials allow light to pass through them only diffusely (i.e. they cannot be seen through clearly), lustrous Lustre is a description of the way light interacts with the surface of a crystal, rock, or mineral. For example, a diamond is said to have an adamantine lustre and pyrite is said to have a metallic lustre. The term is also used to describe other items with a particular sheen (for example, fabric, especially silk and satin, or metals) substance.[7]

Contents

Glass production

Main articles: Glass production Glass production comprehends two types of glass: sheet glass, made by the float glass process, and (ii) glass-container glass and Float glass Float glass is a sheet of glass made by floating molten glass on a bed of molten tin. This method gives the sheet uniform thickness and very flat surfaces. Modern windows are made from float glass. Most float glass is soda-lime glass, but relatively minor quantities of specialty borosilicate and flat panel display glass are also produced using the

Glass ingredients

Quartz sand Sand is a naturally occurring granular material composed of finely divided rock and mineral particles (silica) as main raw material for commercial glass production Oldest mouth-blown window-glass in Sweden Sweden (pronounced /ˈswiːdən/ ), officially the Kingdom of Sweden (Swedish: Konungariket Sverige (help·info)), is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden has land borders with Norway to the west and Finland to the northeast, and it is connected to Denmark by the Öresund Bridge in the south (Kosta Glasbruk Kosta Glasbruk is a Swedish glassworks founded by two foreign officers in Charles XII's army, Anders Koskull and Georg Bogislaus Stael von Holstein, in 1742 . It is located in Kosta (between the cities of Kalmar and Växjö) in the forested Småland province. The surrounding region has become known as the "Kingdom of Crystal" and is now, Småland Småland is a historical province (landskap) in southern Sweden. Småland borders Blekinge, Scania or Skåne, Halland, Västergötland, Östergötland and the island Öland in the Baltic Sea. The name Småland literally means Small land, 1742 Year 1742 was a common year starting on Monday (link will display the full calendar) of the Gregorian calendar (or a common year starting on Friday of the 11-day slower Julian calendar)). In the middle is the mark from the glass blower's Glassblowing is a glassforming technique that involves inflating the molten glass into a bubble, or parison, with the aid of the blowpipe, or blow tube. A person who blows glass is called a glassblower, glassmith, or gaffer pipe.

Pure silica The chemical compound silicon dioxide, also known as silica , is an oxide of silicon with a chemical formula of Si (SiO2) has a "glass melting point"— at a viscosity Viscosity is a measure of the resistance of a fluid which is being deformed by either shear stress or extensional stress. In everyday terms , viscosity is "thickness". Thus, water is "thin", having a lower viscosity, while honey is "thick" having a higher viscosity. Viscosity describes a fluid's internal resistance to 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 aluminum oxide (Al2O3) 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.[8] Soda-lime glasses account for about 90 percent of manufactured glass.

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 eye 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).

Two other common glass ingredients are calumite (an iron industry by-product) and "cullet" (recycled glass). The recycled glass saves on raw materials and energy. However, impurities in the cullet can lead to product and equipment failure.

Finally, fining agents such as sodium sulfate, sodium chloride, or antimony oxide are added to reduce the bubble content in the glass.[8] Glass batch calculation is the method by which the correct raw material mixture is determined to achieve the desired glass composition.

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.[8]

After melting, homogenization and refining (removal of bubbles), the glass is . 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, who created a continuous ribbon of glass using a molten tin bath on which the molten glass flows unhindered under the influence of gravity. The top surface of the glass is subjected to nitrogen under pressure to obtain a polished finish.[9] Container glass for common bottles and jars is formed by blowing and pressing methods. Further glass forming techniques are summarized in the table .

Once the desired form is obtained, glass is usually annealed for the removal of stresses. Surface treatments, 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).

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).[10] 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.[10][11]

In order to make glass from materials with poor glass forming tendencies, novel techniques are used to increase cooling rate, or reduce crystal nucleation triggers. Examples of these techniques include aerodynamic levitation (the melt is cooled whilst floating in a gas stream), splat quenching, (the melt is pressed between two metal anvils) and roller quenching (the melt is poured through rollers).

See also: Optical lens design, Fabrication and testing of optical components

Sol-gel science/technology

Main article: Sol-gel

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]

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 fluoride glasses (fluorozirconates, fluoroaluminates), aluminosilicates, phosphate glasses and chalcogenide glasses.

Under extremes of pressure and temperature solids may exhibit large structural and physical changes which can lead to polyamorphic phase transitions.[12] 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.[13]

Physics of glass

See also Physics of glass
Unsolved problems in physics: What is the nature of the transition between a fluid or regular solid and a glassy phase? What are the physical processes giving rise to the general properties of glasses? 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) is a solid formed by rapid melt quenching.[2][3][4][14] If the cooling is sufficiently rapid (relative to the characteristic crystallization time) then crystallization is prevented and instead the disordered atomic configuration of the supercooled liquid is frozen into the solid state at the glass transition temperature Tg. 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] As in other amorphous solids, the atomic structure of a glass lacks any long range translational periodicity. However, due to chemical bonding characteristics 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]

Glass versus a supercooled liquid

Glass is generally classed as an amorphous solid rather than a liquid.[14][18] Glass displays all the mechanical properties of a solid. 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]

Some people consider glass to be 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 range. However, the glass transition 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, the equilibrium theory of phase transformations in solids does not entirely hold for glass, and hence the glass transition cannot be classed as one of the classical equilibrium phase transformations in solids.[4]

Although the atomic structure of glass shares characteristics of the structure in a supercooled liquid, glass tends to behave as a solid below its glass transition temperature.[21] A supercooled liquid behaves as a liquid, 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.

Behavior of antique glass

The observation that old windows are often thicker at the bottom than at the top is often offered as supporting evidence for the view that glass flows over a matter of centuries. It is then assumed that the glass was once uniform, but has flowed to its new shape, which is a property of liquid.[22] In actuality, the likely reason for this is that when panes of glass were commonly made by glassblowers, the technique used was to spin molten glass so as to create a round, mostly flat and even plate (the crown glass process, described above). This plate was then cut to fit a window. The pieces were not, however, absolutely flat; the edges of the disk became thicker as the glass spun. When actually installed in a window frame, the glass would be placed thicker side down both for the sake of stability and to prevent water accumulating in the lead cames at the bottom of the window.[23] Occasionally such glass has been found thinner side down or thicker on either side of the window's edge, as would be caused by carelessness at the time of installation.

Mass production of glass window panes in the early twentieth century caused a similar effect. In glass factories, molten glass was poured onto a large cooling table and allowed to spread. The resulting glass is thicker at the location of the pour, located at the center of the large sheet. These sheets were cut into smaller window panes with nonuniform thickness. Modern glass intended for windows is produced as float glass and is very uniform in thickness.

Several other points exemplify the misconception of the "cathedral glass" theory:

Some glasses have a glass transition temperature close to or below room temperature. The behavior of a material that has a glass transition close to room temperature depends upon the timescale during which the material is manipulated. If the material is hit it may break like a solid glass, but if the material is left on a table for a week it may flow like a liquid. This simply means that for the fast timescale its transition temperature is above room temperature, but for the slow one it is below. The shift in temperature with timescale is not very large however, as indicated by the transition of polypropylene glycol of −72°C and −71°C over different timescales.[15] To observe window glass flowing as liquid at room temperature we would have to wait a much longer time than any human can exist. Therefore it is safe to consider a glass a solid far enough below its transition temperature: Cathedral glass does not flow because its glass transition temperature is many hundreds of degrees above room temperature. Close to this temperature there are interesting time-dependent properties. One of these is known as aging. Many polymers that we use in daily life such as rubber, polystyrene and polypropylene are in a glassy state but they are not too far below their glass transition temperature. Their mechanical properties may well change over time and this is serious concern when applying these materials in construction.

Physical properties

The following table lists some physical properties of common glasses. Unless otherwise stated, the technical glass compositions and many experimentally determined properties are taken from one large study.[25] Unless stated otherwise, the properties of fused silica (quartz glass) and germania glass are derived from the SciGlass glass database by forming the arithmetic mean of all the experimental values from different authors (in general more than 10 independent sources for quartz glass and Tg of germanium oxide glass). Those values marked in italic font have been interpolated from similar glass compositions (see Calculation of glass properties) due to the lack of experimental data.

Properties Soda-lime glass (for containers)[26] Borosilicate (low expansion, similar to Pyrex, Duran) Glass wool (for thermal insulation) Special optical glass (similar to Lead crystal) Fused silica Germania glass Germanium selenide glass
Chemical composition, wt% 74 SiO2, 13 Na2O, 10.5 CaO, 1.3 Al2O3, 0.3 K2O, 0.2 SO3, 0.2 MgO, 0.01 TiO2, 0.04 Fe2O3 81 SiO2, 12.5 B2O3, 4 Na2O, 2.2 Al2O3, 0.02 CaO, 0.06 K2O 63 SiO2, 16 Na2O, 8 CaO, 3.3 B2O3, 5 Al2O3, 3.5 MgO, 0.8 K2O, 0.3 Fe2O3, 0.2 SO3 41.2 SiO2, 34.1 PbO, 12.4 BaO, 6.3 ZnO, 3.0 K2O, 2.5 CaO, 0.35 Sb2O3, 0.2 As2O3 SiO2 GeO2 GeSe2
Viscosity log(η, Pa·s) = A + B / (T in °C − To) 550–1450°C: A = -2.309 B = 3922 To = 291 550–1450°C: A = -2.834 B = 6668 To = 108 550–1400°C: A = -2.323 B = 3232 To = 318 500–690°C: A = -35.59 B = 60930 To = −741 1140–2320°C: A = -7.766 B = 27913 To = −271.7 515–1540°C: A = -11.044 B = 30979 To = −837
Glass transition temperature, Tg, °C 573 536 551 ~540 1140 526 ± 27[27][28][29] 395 [30]
Coefficient of thermal expansion, ppm/K, ~100–300°C 9 3.5 10 7 0.55 7.3
Density at 20°C, [g/cm3], x1000 to get [kg/m3] 2.52 2.235 2.550 3.86 2.203 3.65 [31] 4.16 [30]
Refractive index nD[32] at 20°C 1.518 1.473 1.531 1.650 1.459 1.608 1.7
Dispersion at 20°C, 104×(nF − nC)[32] 86.7 72.3 89.5 169 67.8 146
Young's modulus at 20°C, GPa 72 65 75 67 72 43.3 [33]
Shear modulus at 20°C, GPa 29.8 28.2 26.8 31.3
Liquidus temperature, °C 1040 1070[34] 1715 1115
Heat capacity at 20°C, J/(mol·K) 49 50 50 51 44 52
Surface tension, at ~1300°C, mJ/m2 315 370 290
Chemical durability, Hydrolytic class, after ISO 719[35] 3 1 3

Color

Common soda-lime float glass appears green in thick sections because of Fe2+ impurities. Main article: Glass coloring and color marking

Color in glass may be obtained by addition of electrically charged ions (or color centers) that are homogeneously distributed, and by precipitation of finely dispersed particles (such as in photochromic glasses).[6] Ordinary soda-lime glass appears colorless to the naked eye when it is thin, although iron(II) oxide (FeO) impurities of up to 0.1 wt%[25] produce a green tint which can be viewed in thick pieces or with the aid of scientific instruments. Further FeO and Cr2O3 additions may be used for the production of green bottles. Sulfur, together with carbon and iron salts, is used to form iron polysulfides and produce amber glass ranging from yellowish to almost black.[36] Manganese dioxide can be added in small amounts to remove the green tint given by iron(II) oxide.

Optical waveguides

The propagation of light through a multi-mode optical fiber. A laser bouncing down an acrylic rod, illustrating the total internal reflection of light in a multimode optical fiber.

Optically transparent materials focus on the response of a material to incoming light waves of a range of wavelengths. Frequency selective optical filters can be utilized to alter or enhance the brightness and contrast of a digital image. Guided light wave transmission via frequency selective waveguides involves the emerging field of fiber optics and the ability of certain glassy compositions as a transmission medium for a range of frequencies simultaneously (multimode optical fiber) with little or no interference between competing wavelengths or frequencies. This resonant mode of energy and data transmission via electromagnetic (light) wave propagation, though low powered, is relatively lossless.

An optical fiber is a cylindrical dielectric waveguide that transmits light along its axis by the process of total internal reflection. The fiber consists of a core surrounded by a cladding layer. To confine the optical signal in the core, the refractive index of the core must be greater than that of the cladding. The index of refraction is a way of measuring the speed of light in a material. (Note: The index of refraction is the ratio of the speed of light in a vacuum to the speed of light in a given medium. (The index of refraction of a vacuum is therefore equal to 1, by definition). The larger the index of refraction, the more slowly light travels in that medium. Typical values for core and cladding of an optical fiber are 1.48 and 1.46, respectively.

When light traveling in a dense medium hits a boundary at a steep angle, the light will be completely reflected. This effect is used in optical fibers to confine light in the core. Light travels along the fiber bouncing back and forth off of the boundary. Because the light must strike the boundary with an angle greater than the critical angle, only light that enters the fiber within a certain range of angles will be propagated. This range of angles is called the acceptance cone of the fiber. The size of this acceptance cone is a function of the refractive index difference between the fiber's core and cladding.

Optical waveguides are used as components in integrated optical circuits (e.g. light-emitting diodes, LEDs) or as the transmission medium in local and long haul optical communication systems. Also of value to the emerging materials scientist is the sensitivity of materials to thermal radiation in the infrared (IR) portion of the EM spectrum. This infrared homing (or "heat-seeking") capability is responsible for such diverse optical phenomena as "night vision" and IR luminescence.

History

See also: Category:Glass history
Obsidian from Lake County, Oregon, USA Roman Cage Cup from the 4th century A.D. Roman glass

Naturally occurring glass, especially obsidian, has been used by many Stone Age societies across the globe for the production of sharp cutting tools and, due to its limited source areas, was extensively traded. But in general, archaeological evidence suggests that the first true glass was made in coastal north Syria, Mesopotamia or Old Kingdom Egypt.[37] Due to Egypt's favorable environment for preservation, the majority of well-studied early glass is found in Egypt, although some of this is likely to have been imported. The earliest known glass objects, of the mid third millennium BC, were beads, perhaps initially created as accidental by-products of metal-working slags or during the production of faience, a pre-glass vitreous material made by a process similar to glazing.[38]

During the Late Bronze Age in Egypt and Western Asia there was an explosion in glass-making technology. Archaeological finds from this period include colored glass ingots, vessels (often colored and shaped in imitation of highly prized wares of semi-precious stones) and the ubiquitous beads. The alkali of Syrian and Egyptian glass was soda ash, sodium carbonate, which can be extracted from the ashes of many plants, notably halophile seashore plants: (see saltwort). The earliest vessels were 'core-wound', produced by winding a ductile rope of glass round a shaped core of sand and clay over a metal rod, then fusing it with repeated reheatings. Threads of thin glass of different colors made with admixtures of oxides were subsequently wound around these to create patterns, which could be drawn into festoons by using metal raking tools. The vessel would then be rolled flat ('marvered') on a slab in order to press the decorative threads into its body. Handles and feet were applied separately. The rod was subsequently allowed to cool as the glass slowly annealed and was eventually removed from the center of the vessel, after which the core material was scraped out. Glass shapes for inlays were also often created in moulds. Much early glass production, however, relied on grinding techniques borrowed from stone working. This meant that the glass was ground and carved in a cold state.

By the 15th century BC extensive glass production was occurring in Western Asia and Egypt. It is thought the techniques and recipes required for the initial fusing of glass from raw materials was a closely guarded technological secret reserved for the large palace industries of powerful states. Glass workers in other areas therefore relied on imports of pre-formed glass, often in the form of cast ingots such as those found on the Ulu Burun shipwreck off the coast of Turkey.

Glass remained a luxury material, and the disasters that overtook Late Bronze Age civilisations seem to have brought glass-making to a halt. It picked up again in its former sites, in Syria and Cyprus, in the ninth century BC, when the techniques for making colorless glass were discovered. The first glassmaking "manual" dates back to ca. 650 BC. Instructions on how to make glass are contained in cuneiform tablets discovered in the library of the Assyrian king Ashurbanipal. In Egypt glass-making did not revive until it was reintroduced in Ptolemaic Alexandria. Core-formed vessels and beads were still widely produced, but other techniques came to the fore with experimentation and technological advancements. During the Hellenistic period many new techniques of glass production were introduced and glass began to be used to make larger pieces, notably table wares. Techniques developed during this period include 'slumping' viscous (but not fully molten) glass over a mould in order to form a dish and 'millefiori' (meaning 'thousand flowers') technique, where canes of multi-colored glass were sliced and the slices arranged together and fused in a mould to create a mosaic-like effect. It was also during this period that colorless or decolored glass began to be prized and methods for achieving this effect were investigated more fully.[7]

According to Pliny the Elder, Phoenician traders were the first to stumble upon glass manufacturing techniques at the site of the Belus River. Georgius Agricola, in De re metallica, reported a traditional serendipitous "discovery" tale of familiar type:

"The tradition is that a merchant ship laden with nitrum being moored at this place, the merchants were preparing their meal on the beach, and not having stones to prop up their pots, they used lumps of nitrum from the ship, which fused and mixed with the sands of the shore, and there flowed streams of a new translucent liquid, and thus was the origin of glass."[39]

This account is more a reflection of Roman experience of glass production, however, as white silica sand from this area was used in the production of Roman glass due to its low impurity levels.

During the first century BC glass blowing was discovered on the Syro-Palestinian coast, revolutionising the industry and laying the way for the explosion of glass production that occurred throughout the Roman world. It was the Romans who began to use glass for architectural purposes, with the discovery of clear glass (through the introduction of manganese oxide), in Alexandria ca. AD 100. Cast glass windows, albeit with poor optical qualities, thus began to appear in the most important buildings in Rome and the most luxurious villas of Herculaneum and Pompeii. Over the next 1,000 years glass making and working continued and spread through southern Europe and beyond.

South Asia

Indigenous development of glass technology in South Asia may have begun in 1730 BC.[40] Evidence of this culture includes a red-brown glass bead along with a hoard of beads dating to 1730 BC, making it the earliest attested glass from the Indus Valley locations.[40] Glass discovered from later sites dating from 600–300 BC displays common color.[40]

Chalcolithic evidence of glass has been found in Hastinapur, India.[41] Some of the texts which mention glass in India are the Shatapatha Brahmana and Vinaya Pitaka.[41] However, the first unmistakable evidence in large quantities, dating from the 3rd century BC, has been uncovered from the archaeological site in Taxila, Pakistan.[41]

By the beginning of the Common Era, glass was being used for ornaments and casing in South Asia.[41] Contact with the Greco-Roman world added newer techniques, and Indians artisans mastered several techniques of glass molding, decorating and coloring by the early centuries of the Common Era.[41] Satavahana period of India further reveals short cylinders of composite glass, including those displaying a lemon yellow matrix covered with green glass.[42]

Romans

A full discussion of Roman glass making and working can be found on the Roman glass page.

Anglo-Saxon world

Evidence for glass making, working and use in the 5th to 8th centuries in England is discussed in the Anglo-Saxon glass page.

Islamic world

Main article: Islamic glass

The Arab poet al-Buhturi (820–897) described the clarity of such glass, "Its color hides the glass as if it is standing in it without a container."[43]

Stained glass was also first produced by Muslim architects in Southwest Asia using colored glass rather than stone.[citation needed] In the 8th century, the Arab chemist Jabir ibn Hayyan (Geber) scientifically described 46 original recipes for producing colored glass in Kitab al-Durra al-Maknuna (The Book of the Hidden Pearl), in addition to 12 recipes inserted by al-Marrakishi in a later edition of the book.[44]

The parabolic mirror was first described by Ibn Sahl in his On the Burning Instruments in the 10th century, and later described again in Ibn al-Haytham's On Burning Mirrors and Book of Optics (1021).[45] By the 11th century, clear glass mirrors were being produced in Islamic Spain. The first glass factories were also built by Muslim craftsmen in the Islamic world.[citation needed] The first glass factories in Christian Europe were later built in the 11th century by Muslim Egyptian craftsmen in Corinth, Greece.[46]

Medieval Europe

A 16th-century stained glass window

Glass objects from the 7th and 8th centuries have been found on the island of Torcello near Venice. These form an important link between Roman times and the later importance of that city in the production of the material. Around 1000 AD, an important technical breakthrough was made in Northern Europe when soda glass, produced from white pebbles and burnt vegetation was replaced by glass made from a much more readily available material: potash obtained from wood ashes. From this point on, northern glass differed significantly from that made in the Mediterranean area, where soda remained in common use.[47]

Until the 12th century, stained glass – glass to which metallic or other impurities had been added for coloring – was not widely used.

The 11th century saw the emergence in Germany of new ways of making sheet glass by blowing spheres. The spheres were swung out to form cylinders and then cut while still hot, after which the sheets were flattened. This technique was perfected in 13th century Venice.

The Crown glass process was used up to the mid-19th century. In this process, the glassblower would spin approximately 9 pounds (4 kg) of molten glass at the end of a rod until it flattened into a disk approximately 5 feet (1.5 m) in diameter. The disk would then be cut into panes.

Late medieval Northern Europe

Glass making in late medieval Northern Europe is discussed in the article on Forest glass.

Murano glassmaking

Main articles: Murano glass and Venetian glass

The center for glassmaking from the 14th century was the island of Murano, which developed many new techniques and became the center of a lucrative export trade in dinnerware, mirrors, and other luxury items. What made Venetian Murano glass significantly different was that the local quartz pebbles were almost pure silica, and were ground into a fine clear sand that was combined with soda ash obtained from the Levant, for which the Venetians held the sole monopoly. The clearest and finest glass is tinted in two ways: firstly, a small or large amount of a natural coloring agent is ground and melted with the glass. Many of these coloring agents still exist today; for a list of coloring agents, see below. Black glass was called obsidianus after obsidian stone. A second method is apparently to produce a black glass which, when held to the light, will show the true color that this glass will give to another glass when used as a dye. [48]

The Venetian ability to produce this superior form of glass resulted in a trade advantage over other glass producing lands. Murano’s reputation as a center for glassmaking was born when the Venetian Republic, fearing fire might burn down the city’s mostly wood buildings, ordered glassmakers to move their foundries to Murano in 1291. Murano's glassmakers were soon the island’s most prominent citizens. Glassmakers were not allowed to leave the Republic. Many took a risk and set up glass furnaces in surrounding cities and as far afield as England and the Netherlands.

Glass art

Main article: Glass art A glass sculpture “The Sun” at the “Gardens of Glass” exhibition in Kew Gardens, London, England. The piece is 13 feet (4 metres) high and made from 1000 separate glass objects. A vase being created at the Reijmyre glassworks, Sweden Paperweight with items inside the glass, Corning Museum of Glass

Beginning in the late 20th century, glass started to become highly collectible as art. Works of art in glass can be seen in a variety of museums, including the Chrysler Museum, the Museum of Glass in Tacoma, the Metropolitan Museum of Art, the Toledo Museum of Art, and Corning Museum of Glass, in Corning, NY, which houses the world's largest collection of glass art and history, with more than 45,000 objects in its collection.[49]

Several of the most common techniques for producing glass art include: blowing, kiln-casting, fusing, slumping, pate-de-verre, flame-working, hot-sculpting and cold-working. Cold work includes traditional stained glass work as well as other methods of shaping glass at room temperature. Glass can also be cut with a diamond saw, or copper wheels embedded with abrasives, and polished to give gleaming facets; the technique used in creating Waterford crystal [50]. Art is sometimes etched into glass via the use of acid, caustic, or abrasive substances. Traditionally this was done after the glass was blown or cast. In the 1920s a new mould-etch process was invented, in which art was etched directly into the mould, so that each cast piece emerged from the mould with the image already on the surface of the glass. This reduced manufacturing costs and, combined with a wider use of colored glass, led to cheap glassware in the 1930s, which later became known as Depression glass[51]. As the types of acids used in this process are extremely hazardous, abrasive methods have gained popularity.

Objects made out of glass include not only traditional objects such as vessels (bowls, vases, bottles, and other containers), paperweights, marbles, beads, but an endless range of sculpture and installation art as well. Colored glass is often used, though sometimes the glass is painted, innumerable examples exist of the use of stained glass.

The Harvard Museum of Natural History has a collection of extremely detailed models of flowers made of painted glass. These were lampworked by Leopold Blaschka and his son Rudolph, who never revealed the method he used to make them. The Blaschka Glass Flowers are still an inspiration to glassblowers today. [52]

See also

References

  1. ^ ASTM definition of glass from 1945; also: DIN 1259, Glas – Begriffe für Glasarten und Glasgruppen, September 1986
  2. ^ a b Zallen, R. (1983). The Physics of Amorphous Solids. New York: John Wiley.
  3. ^ a b Cusack, N. E. (1987). The physics of structurally disordered matter: an introduction. Adam Hilger in association with the University of Sussex press.
  4. ^ a b c Elliot, S. R. (1984). Physics of Amorphous Materials. Longman group ltd.
  5. ^ Horst Scholze (1991). Glass – Nature, Structure, and Properties. Springer. ISBN 0-387-97396-6.
  6. ^ a b c d Werner Vogel (1994). Glass Chemistry (2 ed.). Springer-Verlag Berlin and Heidelberg GmbH & Co. K. ISBN 3540575723.
  7. ^ a b Douglas, R. W. (1972). A history of glassmaking. Henley-on-Thames: G T Foulis & Co Ltd. ISBN 0854291172.
  8. ^ a b c B. H. W. S. de Jong, "Glass"; in "Ullmann's Encyclopedia of Industrial Chemistry"; 5th edition, vol. A12, VCH Publishers, Weinheim, Germany, 1989, ISBN 3-527-20112-5, p 365–432.
  9. ^ PFG Glass
  10. ^ a b Glass melting, Pacific Northwest National Laboratory
  11. ^ Glass melting in the laboratory
  12. ^ P. F. McMillan "Polyamorphic transformations in liquids and glasses" Journal of Materials Chemistry 14, 1506–1512 (2004)
  13. ^ carbon dioxide glass created in the lab 15 June 2006, www.newscientisttech.com. Retrieved 3 August 2006
  14. ^ a b S. A. Baeurle et al. "On the glassy state of multiphase and pure polymer materials" Polymer 47, 6243–6253 (2006)
  15. ^ a b "Folmer, J. C. W.; Franzen, Stefan." Study of polymer glasses by modulated differential scanning calorimetry in the undergraduate physical chemistry laboratory" Journal of Chemical Education (2003), 80(7), 813
  16. ^ P.S. Salmon "Order within disorder" Nature Materials, 1(87), (2002)
  17. ^ M.I. Ojovan, W.E. Lee "Topologically disordered systems at the glass transition" J. Phys.: Condensed Matter, 18, 11507–11520 (2006)
  18. ^ a b c d Philip Gibbs. "Is glass liquid or solid?". http://math.ucr.edu/home/baez/physics/General/Glass/glass.html. Retrieved on 2007-03-21.
  19. ^ "Philip Gibbs" Glass Worldwide, (may/june 2007), pp 14–18
  20. ^ Jim Loy. "Glass Is A Liquid?". http://www.jimloy.com/physics/glass.htm. Retrieved on 2007-03-21.
  21. ^ Florin Neumann. "Glass: Liquid or Solid – Science vs. an Urban Legend". http://dwb.unl.edu/Teacher/NSF/C01/C01Links/www.ualberta.ca/~bderksen/florin.html. Retrieved on 2007-04-08.
  22. ^ Chang, Kenneth (2008-07-29). "The Nature of Glass Remains Anything but Clear". New York Times. http://www.nytimes.com/2008/07/29/science/29glass.html?ex=1375070400&en=048ade4011756b24&ei=5124&partner=permalink&exprod=permalink. Retrieved on 2008-07-29.
  23. ^ Dr Karl's Homework: Glass Flows
  24. ^ "Do Cathedral Glasses Flow?" Am. J. Phys., 66 (May 1998), pp 392–396
  25. ^ a b "High temperature glass melt property database for process modeling"; Eds.: Thomas P. Seward III and Terese Vascott; The American Ceramic Society, Westerville, Ohio, 2005, ISBN 1-57498-225-7
  26. ^ Soda-lime glass for containers is slightly different from soda-lime glass for windows (also called flat glass or float glass). Float glass has a higher magnesium oxide content as compared to container glass, and a lower silica and calcium oxide content. For further details see main article Soda-lime glass.
  27. ^ A.J. Leadbettera and A.C. Wrigh "Diffraction studies of glass structure: II. The structure of vitreous germania" Journal of non-crystalline solids, 7:37–52 (1972)
  28. ^ M. Micoulaut et al. "Simulated structural and thermal properties of glassy and liquid germania" Physical Review E, 73:031504 (2006)
  29. ^ 35 Tg data for GeO2 from SciGlass 6.7
  30. ^ a b Kotkata et al. "Effect of thallium on the optical properties of amorphous GeSe2 and GeSe4 films" J. Phys. D: Appl. Phys. 27 pp 623–627 (1994)
  31. ^ P. S. Salmon et al. "Glass Fragility and Atomic Ordering on the Intermediate and Extended Range" Physical Review Letters, 96, 235502 (2006)
  32. ^ a b The subscript D indicates that the refractive index n was measured at a wavelength λ of 589.29 nm, F and C indicate 486.13 nm (blue) and 656.27 nm (red) respectively (see article Fraunhofer lines)
  33. ^ L. G. Hwa and W.C. Chao "Velocity of sound and elastic properties of lanthanum gallo-germanate glasses" Materials Chemistry and Physics, 94, 37–41 (2005)
  34. ^ Valid for glass composition, wt%: 80.7 SiO2, 13.1 B2O3, 4.1 Na2O, 2.1 Al2O3; Reference: Baak N. T. E. A. and Rapp C. F., GB Patent No. 1132885 Cl C 03 C 3/04, Abridg. Specif., 1968; Assignee: Owens-Illinois, Inc. (US).
  35. ^ International Organization for Standardization, Procedure 719 (1985)
  36. ^ Substances Used in the Making of Coloured Glass 1st.glassman.com (David M Issitt). Retrieved 3 August 2006
  37. ^ "Glass Online: The History of Glass". http://www.glassonline.com/infoserv/history.html. Retrieved on 2007-10-29.
  38. ^ True glazing over a ceramic body was not used until many centuries after the production of the first glass.
  39. ^ Agricola, Georgius, De re metallica, translated by Herbert Clark Hoover and Lou Henry Hoover, Dover Publishing. De Re Metallica Trans. by Hoover Online Version Page 586 Retrieved = 12 September 2007
  40. ^ a b c Gowlett 1997, page 276–277
  41. ^ a b c d e Ghosh 1990, page 219
  42. ^ "Ornaments, Gems etc." (Ch. 10) in Ghosh 1990
  43. ^ Ahmad Y Hassan, Assessment of Kitab al-Durra al-Maknuna, History of Science and Technology in Islam.
  44. ^ Ahmad Y Hassan, The Manufacture of Coloured Glass, History of Science and Technology in Islam.
  45. ^ Roshdi Rashed (1990), "A Pioneer in Anaclastics: Ibn Sahl on Burning Mirrors and Lenses", Isis 81 (3), p. 464–491 [464–468].
  46. ^ Ahmad Y Hassan, Transfer Of Islamic Technology To The West, Part III: Technology Transfer in the Chemical Industries, History of Science and Technology in Islam.
  47. ^ Donny L. Hamilton. "Glass Conservation". Conservation Research Laboratory, Texas A&M University. http://nautarch.tamu.edu/class/anth605/File5.htm. Retrieved on 2007-03-21.
  48. ^ Georg Agricola De Natura Fossilium, Textbook of Mineralogy, M.C. Bandy, J. Bandy, Mineralogical Society of America, 1955, Page 111 Section on Murano Glass, De Natura Fossilium Retrieved 2007-09-12
  49. ^ "Corning Museum of Glass". http://www.cmog.org/index.asp?pageId=1276. Retrieved on 2007-10-14.
  50. ^ "Waterford Crystal Vistors Centre". http://www.waterfordvisitorcentre.com/. Retrieved on 2007-10-19.
  51. ^ "Depression Glass". http://www.glassonweb.com/articles/article/201/. Retrieved on 2007-10-19.
  52. ^ the Harvard Museum of Natural History's page on the exhibit

Bibliography

External links

Look up glass in Wiktionary, the free dictionary.
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Glass science topics
Basics Glass definition · Is glass a liquid or a solid? · Glass-liquid transition · Physics of glass · Supercooling
Glass formulation AgInSbTe · Bioglass · Borophosphosilicate glass · Borosilicate glass · Ceramic glaze · Chalcogenide glass · Cobalt glass · Cranberry glass · Crown glass · Flint glass · Fluorosilicate glass · Fused quartz · GeSbTe · Gold ruby glass · Lead glass · Milk glass · Phosphosilicate glass · Photochromic lens glass · Silicate glass · Soda-lime glass · Sodium hexametaphosphate · Soluble glass · Ultra low expansion glass · Uranium glass · Vitreous enamel · ZBLAN
Glass-ceramics Bioactive glass · CorningWare · Glass-ceramic-to-metal seals · Macor · Zerodur
Glass preparation Annealing · Chemical vapor deposition · Glass batch calculation Glass melting · Glass modeling · Ion implantation · Liquidus temperature · Sol-gel technique · Viscosity
Optics Dispersion · Gradient index optics · Hydrogen darkening · Optical amplifier · Optical fiber · Optical lens design · Photochromic lens · Photosensitive glass · Refraction · Transparent materials
Surface modification Anti-reflective coating · Chemically strengthened glass · Corrosion · Dealkalization · DNA microarray · Hydrogen darkening · Insulated glazing · Porous glass · Self-cleaning glass · Sol-gel technique · Toughened glass
Diverse topics Diffusion · Glass-coated wire · Glass databases · Glass electrode · Glass fiber reinforced concrete · Glass history · Glass ionomer cement · Glass microspheres · Glass-reinforced plastic · Glass science institutes · Glass-to-metal seal · Porous glass · Prince Rupert's Drops · Radioactive waste vitrification · Windshield
Glass forming techniques
Commercial techniques Float glass process · Blowing and pressing (containers) · Extrusion / Drawing (fibers, glasswool) · Drawing (optical fibers) · Precision glass moulding · Overflow downdraw method · Pressing · Casting · Cutting · Flame polishing · Chemical polishing · Diamond turning · Rolling
Artistic and historic techniques Beadmaking · Blowing · Blown plate · Broad sheet · Caneworking · Crown glass · Cylinder blown sheet · Engraving · Etching · Fourcault process · Fusing · Lampworking · Machine drawn cylinder sheet · Millefiori · Polished plate · Slumping · Stained glass fusing · Stained glass production
See also Glossary of glass art terms
Glass makers and brands
Contemporary companies Anchor Hocking · Arc International · Ardagh · Armashield · Asahi · Aurora Glass Foundry · Baccarat · Blenko Glass Company · Bodum · Corning · Dartington Crystal · Daum · Edinburgh Crystal · Fanavid · Fenton Art Glass Company · Firozabad glass industry · Franz Mayer · Glava · Glaverbel · Hardman & Co. · Heaton, Butler and Bayne · Holmegaard Glassworks · Holophane · Hoya · Kingdom of Crystal · Kokomo Opalescent Glass Works · Kosta Glasbruk · Libbey Owens Ford · Liuli Gongfang · Iittala · Johns Manville · Mats Jonasson Målerås · Moser Glass · Mosser Glass · Nippon Sheet Glass · Orrefors Glasbruk · Osram · Owens Corning · Owens-Illinois · Pauly & C. - Compagnia Venezia Murano · PPG · Pilkington · Preciosa · Quinn Group · Riedel · Royal Leerdam Crystal · Saint-Gobain · Samsung Corning Precision Glass · Schonbek · Schott · Shrigley and Hunt · Steuben Glass · Sterlite Optical Technologies · Swarovski · Tyrone Crystal · Val Saint Lambert · Verrerie of Brehat · Waterford · Watts & Co · World Kitchen · Xinyi Glass · Zwiesel
Historic companies Bakewell Glass · Belmont Glass Company · Boston and Sandwich Glass Company · Carr Lowrey Glass Company · Cambridge Glass · Chance Brothers · Clayton and Bell · Dunbar Glass · Fostoria Glass Company · General Glass Industries · Alexander Gibbs · Hazel-Atlas · Heisey · Hemingray Glass Company · Knox Glass Bottle Company · Lavers, Barraud and Westlake · Manufacture royale de glaces de miroirs · Morris & Co. · Old Dominion Glass Company · James Powell and Sons · Ravenhead glass · The Root Glass Company · Sneath Glass Company · Ward and Hughes · Westmoreland Glass Company · Whitall Tatum Company · White Glass Company · Worshipful Company
Glassmakers John Adams · Richard M. Atwater · Frederick Carder · Irving Wightman Colburn · Henry Crimmel · Henry Clay Fry · Friedrich · A. H. Heisey · Libbey · Antonio Neri · Alastair Pilkington · Salviati · Otto Schott · S. Donald Stookey · John M. Whitall
Trademarks and brands Bohemian glass · Bomex · Burmese glass · Chevron bead · Corelle · CorningWare · Cranberry glass · Cristallo · Duran · Endural · Favrile · Fire King · Gold Ruby · MACOR · Murano glass · Opaline glass · Pyrex · Ravenhead glass · Tiffany glass · Vitrite · Vitrolite · Vycor · Waterford Crystal · Wood's glass · Zerodur

Categories: Glass | Glass art | Glass history | Dielectrics | Recyclable materials | Packaging materials | Materials science | Sculpture materials

 

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