Tiffany glass

History of Tiffany Glass

Tiffany glass is the generic name used to describe the many and varied types of glass developed and produced by Louis Comfort Tiffany, (1848-1933), one of the most famous stained glass artists of the United States; he was remembered not only for his windows but for decorative glass objects as well, in particular the so-called Tiffany lamps.

Tiffany was an interior designer, and in 1878 his interest turned towards the creation of stained glass, when he opened his own studio and glass foundry because he was unable to find the types of glass that he desired in interior decoration.

Tiffany Glass

Most people think of Tiffany glass as decorative bronze lamps with intricate multicolored, stained-glass shades, but it actually includes other glass products, including solid color windows, painted art glass shades and lamps, and flat and pressed glass. Tiffany glass pieces were incorporated into homes, most notably in lamp and window construction. The glass work was used in the homes of the wealthy, but also in public buildings.

Tiffany glass not only incorporates the color into the glass, but also tonal variations and texture, as well as use tonal variations to suggest depth. The pieces of glass were not evenly colored but were pieces of opalescent window glass made by combining and manipulating several colors to create an unprecedented range of hues and three-dimensional effects. Thus the tiffany windows look like paintings, which were therefore in great demand.

The Preston Bradley Hall dome put in place in Chicago's first public library in 1897 features more than 1,000 square feet of Tiffany glass. (Preston Bradley Hall is now home to the Chicago Cultural Center.)

Types of Tiffany glass

1. Opalescent glass

Opalescent glass is commonly used to describe glass where more than one color is present, being fused during the manufacture, as against flashed glass in which two colors may be laminated, or silver stained glass where a solution of silver nitrate is superficially applied, turning red glass to orange and blue glass to green. Some opalescent glass was used by several stained glass studios in England.

Opalescent glass is made with a combination of white glass and a cathedral color. The opacity of this type of glass is in relation to the amount of white glass used in its creation. Dense opal base glass uses a higher consistency of white glass than light opal base glass. Because of this change in mixtures, dense opal base glass is much more opaque than light opal base glasses.

Opalescent glass radiates especially deep, vibrant hues to achieve pictorial effects of unsurpassed beauty. This stunning stained glass piece features transparent enamels, silk-screened and kiln-fired on hand-rolled glass.

Opalescent glass is made in a number of ways, including as a single colour; with the pigments that give the glass a streaky, mottled, or cloudy appearance; and with or without a surface texture. It can be both a most beautiful and challenging glass with which to work. This is because the pigments are mixed into opalescent glass by hand during manufacture, with the result that the color patterns and tones in the glass are never exactly the same in any two sheets.

Opalescent glass has one characteristic that transparent glass does not: namely, that it can be seen in both transmitted and reflected light. Opalescent glass has color impregnated into it to the extent that the pigmentation is visible by light rays reflecting off it. It can be seen as well as seen through.

2. Favrile Glass

Favrile glass often has a distinctive characteristic that is common in some glass from Classical antiquity: it possesses a superficial iridescence. This iridescence causes the surface to shimmer, but also causes a degree of opacity. This iridescent effect of the glass was obtained by mixing different colors of glass together while hot. Favrile is different from other iridescent glasses because its color is not just on the surface, but imbedded in the glass.

Some of the distinguishing colors in Favrile glass includes "Gold Lustre", Samian Red"," Mazarin Blue", "Tel-al-amana" (or Turquoise Blue), and Aquamarine. Favrile was the first art glass to be used in stained-glass windows, as Tiffany first thought of the idea of making patterns in windows based shapes and colors.

3. Streamer Glass

Streamer glass refers to a sheet of glass with a pattern of glass strings affixed to its surface. Tiffany made use of such textured glass to represent, for example, twigs, branches and grass.

Streamers are prepared from very hot molten glass, gathered at the end of a punty (pontil) that is rapidly swung back and forth and stretched into long, thin strings that rapidly cool and harden. These hand-stretched streamers are pressed on the molten surface of sheet glass during the rolling process, and become permanently fused.

4. Fracture Glass

Fracture glass refers to a sheet of glass with a pattern of irregularly shaped, thin glass wafers affixed to its surface. Fracture glass is made from paper-thin blown shards or flakes of intensely colored glass fused to the bottom of sheets during the rolling process. Tiffany made use of such textured glass to represent, for example, foliage seen from a distance.

The irregular glass wafers, called fractures, are prepared from very hot, colored molten glass, gathered at the end of a blowpipe. A large bubble is forcefully blown until the walls of the bubble rapidly stretch, cool and harden. The resulting glass bubble has paper-thin walls and is immediately shattered into shards. These hand blown shards are pressed on the surface of the molten glass sheet during the rolling process, to which they become permanently fused.

5. Fracture-streamer Glass

Fracture-Streamer glass is fracture glass combined with hand-stretched streamers or strings of glass during the rolling process. Fracture-streamer glass refers to a sheet of glass with a pattern of glass strings, and irregularly shaped, thin glass wafers, affixed to its surface. Tiffany made use of such textured glass to represent, for example, twigs, branches and grass, and distant foliage.

The “fractures” are created by the addition of thin blown flakes of intensely colored glass, while the “streamers” are pulled or drawn strings of intense colors. Both fractures and streamers are quick-fused to the bottom of sheets during the rolling process.

Fracture and streamer glass is used primarily for backgrounds; the fractures suggest multitudinous leaves or flowers in the distance, while the streamers suggest twigs or stems. For this reason, fracture colors are usually selected to correspond to the colors used in leaf or flower foregrounds.

6. Ripple Glass

Ripple glass refers to a sheet of textured glass with marked surface waves. The texture is created during the glass sheet-forming process. A sheet is formed from molten glass with a roller that spins on it, while travelling forward. Normally the roller spins at the same speed as its own forward motion, and the resulting sheet has a smooth surface. In the manufacture of rippled glass, the roller spins faster than its own forward motion. The rippled effect is retained as the glass cools.

In order to cut ripple glass, the sheet may be scored on the smoother side with a carbide glass cutter, and broken at the score line with breaker-grozier pliers.

7. Ring Mottle Glass

Ring mottle glass is an opalescent glass in which rates of crystal growth have been controlled to create ring-shaped areas of opacity. The effect is a visual surface mottling. Ring mottle glass refers to sheet glass with a pronounced mottle created by localized, heat-treated opacification and crystal-growth dynamics. Tiffany's distinctive style exploited glass containing a variety of motifs such as those found in ring mottle glass, and he relied minimally on painted details.

This type of glass has a locally varying opacity; the “rings” are more opaque than the surrounding matrix. Ring mottled glass is used to provide color and image gradation that is non-streaky, or non-linear. The naturally rounded shape of each ring breaks up the more typical streakiness of stained glass. The artist, using ring mottles, can create shading and imagery unavailable from other glass types.

8. Drapery Glass

Glass sheets with multiple dramatic folds, likened to those in hanging drapes. Drapery glass refers to a sheet of heavily folded glass that suggests fabric folds. Tiffany made abundant use of drapery glass in ecclesiastical stained glass windows to add a 3-dimensional effect to flowing robes and angel wings, and to imitate the natural coarseness of magnolia petals.

To create drapery glass, the molten glass is shaped by taking a hand held roller and using it like a rolling pin to create "speed bumps" on the surface. It can also be tugged and pulled by hand using steel tongs to create the deep fabric-like folds in the surface. It is easy for the glassmakers to get burnt while making this unusual glass and extreme care must be taken while rolling the glass.

Bullet Proof Glass

Bullet proof glass or bullet resistant glass refers to any type of glass that is built to stand up against being penetrated by bullets. Although the public uses the term ‘bullet proof glass’, generally within the industry itself it is referred to as bullet-resistant glass, because there is no feasible way to create consumer-level glass that can truly be proof against bullets.

Bullet proof glass is usually constructed using a strong but transparent material such as polycarbonate thermoplastic or by using layers of laminated glass. The desired result is a material with an appearance and light-transmitting behavior of standard glass but offers varying degrees of protection from small arms fire.

The polycarbonate layer, usually consisting of products such as Armormax, Makroclear, Cyrolon, Lexan or Tuffak, is often sandwiched between layers of regular glass. The use of plastic in the laminate provides impact-resistance, such as physical assault with a hammer, an axe, etc. The plastic provides little in the way of bullet-resistance. The glass, which is much harder than plastic, flattens the bullet and thereby prevents penetration. This type of bullet proof glass is usually 70–75 mm (2.8–3.0 in) thick.

Bullet proof glass constructed of laminated glass layers is built from glass sheets bonded together with polyvinyl butyral, polyurethane or ethylene-vinyl acetate. This type of bullet proof glass has been in regular use on combat vehicles since World War II; it is typically about 100–120 mm (3.9–4.7 in) thick and is usually extremely heavy.

Working Principle of the Bullet Resistant Glass

In the bullet proof glass, the Laminate-layers of tough plastic called polycarbonate sandwiched in between the pieces of toughened glass make the glass ten times thicker than the ordinary glass and it is very heavy. If someone fires a bullet at an ordinary piece of glass, the glass can't bend and absorb the energy. So the glass shatters and the bullet carries on through with hardly any loss of momentum. That's why ordinary glass offers no protection against bullets.

But when a bullet strikes bullet proof glass, its energy spreads out sideways through the layers. Because the energy is divided between a number of different pieces of glass and plastic, and spread over a large area, it is quickly absorbed. The bullet slows down so much that it no longer has enough energy to pierce through—or to do much damage if it does so. Although the glass panes do break, the plastic layers stop them flying apart.

Advances in bullet resistant glass have led to the invention of one-way bullet resistant glass, such as used in some bank armored cars. This glass will resist incoming small arms fire striking the outside of the glass, but will allow those on the other side of the glass, such as guards firing from inside the armored car, to fire through the glass at the exterior threat.

One-way Bullet Proof Glass

One-way bullet proof glass is usually made up of two layers, a brittle layer on the outside and a flexible one on the inside. When a bullet is fired from the outside it hits the brittle layer first, shattering an area of it. This shattering absorbs some of the bullet's kinetic energy, and spreads it on a larger area. When the slowed bullet hits the flexible layer, it is stopped. However, when a bullet is fired from the inside, it hits the flexible layer first. The bullet penetrates the flexible layer because its energy is focused on a smaller area; the brittle layer then shatters outward due to the flexing of the inner layer and does not hinder the bullet's progress.

Advancement

The field of bullet proof glass is constantly developing, and there are a number of military projects underway to create lighter-weight, more defensive forms of bullet proof glass. One of the most promising is the use of aluminum oxynitride in the outer layer, in place of a polymer layer.

U.S. military researchers are moving quickly to develop this new class of transparent armour incorporating aluminium oxynitride (Trade name: ALON) as the outside "strike plate" layer. It performs much better than traditional glass/polymer laminates. Aluminium oxynitride "glass" can't defeat threats like the .50 caliber armor piercing rounds using material that is not prohibitively heavy. This more resistant-glass that can be used in military assault vehicles and aircraft.

Applications

Bullet Resistant glasses have a wide range of applications as follows:

• Banks
• Government Buildings
• Convenience Stores
• Churches
• Schools
• Check Cashing Stores
• Liquor Stores
• Post Offices
• Jewelry Stores
• Art Galleries

Glass Types

Flat Glass

Flat glass is the basic material that goes into all types of glass that we see (and see through) every day: All flat glass is made in the form of flat sheets. But some of it, such as that used in automobile windshields, is reheated and sagged (curved) over moulds. It is used to make windscreens and windows for automobiles and transport, and windows and façades for houses and buildings. It is also used, in much smaller quantities, for many other applications like interior fittings and decoration, furniture, "street furniture" (like for bus stops), appliances and electronics, solar energy equipment, and others.

Annealed glass

Annealed glass is the basic flat glass product that is the first result of the float process. It is the common glass that tends to break into large, jagged shards. It is used in some end products -- often in double-glazed windows, for example. It is also the starting material that is turned into more advanced products through further processing such as laminating, toughening, coating, etc.

Laminated Glass

Laminated glass is made of two or more layers of glass with one or more "interlayer’s" of polymeric material bonded between the glass layers. Laminated glass is produced using one of two methods:

1. Poly Vinyl Butyral (PVB) laminated glass is produced using heat and pressure to sandwich a thin layer of PVB between layers of glass. On occasion, other polymers such as Ethyl Vinyl Acetate (EVA) or Polyurethane (PU) are used. This is the most common method.
2. For special applications, Cast in Place (CIP) laminated glass is made by pouring a resin into the space between two sheets of glass that are held parallel and very close to each other.
   

Laminated glass offers many advantages. Safety and security are the best-known of these -- rather than shattering on impact, laminated glass is held together by the interlayer, reducing the safety hazard associated with shattered glass fragments, as well as, to some degree, the security risks associated with easy penetration. But the interlayer also provides a way to apply several other technologies and benefits, such as coloring, sound dampening, resistance to fire, ultraviolet filtering, and other technologies that can be embedded in or with the interlayer.
Laminated glass is used extensively in building and housing products and in the automotive and transport industries.

Alarm Glass

This is a special laminated glass designed and manufactured for security purposes. The inter-layer is embedded with a very thin wire and then “sandwiched” between two or more sheets of glass. The wire forms an electrical circuit which activates an alarm when the glass is forced.

Reflective Glass

Reflective Glass is an ordinary float glass with a metallic coating to reduce solar heat. This special metallic coating also produces a mirror effect, preventing the subject from seeing through the glass. It is mainly used in façades. Reflective glasses are mainly manufactured by two different process such as Production Pyrolitic (On-Line) and Vacuum (magnetron) Process (off-line).

Anti-reflective Glass

This is float glass with a specially-designed coating which reflects a very low percentage of light. It offers maximum transparency and optical clarity, allowing optimum viewing through the glass at all times. The clarity of vision makes anti-reflective glass suitable for all applications where glass should be transparent such as exteriors, shop-fronts, commercial frontages and glazing where vision is important, particularly at nighttime. This glass can also be used in interiors for high quality picture framing, display cabinets, interior display windows and dividing screens.

Fire-resistant Glass

This can be classified into two categories:

1. Heat-transmitting Glass: Heat-resistant glass is high in silica and usually contains boric oxide. It expands little when heated, so it can withstand great temperature changes without cracking. This contains flames and inflammable gas for a short period of time but does not prevent the transmission of heat to the other side of the glazing. These include wired glass and reinforced laminated glass. This type of glasses is widely used in cookware and other household equipment, and in many types of industrial gear.
2. Fire-insulating Glass: This contains flames and inflammable gas for a longer period of time and prevents not only the transmission of flames and smoke, but also of heat to the other side of glazing

Tempered (toughened) Glass

Toughened glass is made from annealed glass treated with a thermal tempering process. A sheet of annealed glass is heated to above its "annealing point" of 600 °C; its surfaces are then rapidly cooled while the inner portion of the glass remains hotter. The different cooling rates between the surface and the inside of the glass produces different physical properties, resulting in compressive stresses in the surface balanced by tensile stresses in the body of the glass.
These counteracting stresses give toughened glass its increased mechanical resistance to breakage, and are also, when it does break, what cause it to produce regular, small, typically square fragments rather than long, dangerous shards that are far more likely to lead to injuries. Toughened glass also has an increased resistance to breakage as a result of stresses caused by different temperatures within a pane.

This type of glass is mainly intended for glass façades, sliding doors, building entrances, bath and shower enclosures and other purposes that require superior strength and safety.

Low-emission Glass

Glass that has a low-emissivity coating applied to it in order to control heat transfer through windows. Windows manufactured with low-E coatings typically cost about 10–15% more than regular windows, but they reduce energy loss by as much as 30–50%.

A low-E coating is a microscopically thin, virtually invisible, metal or metallic oxide layer deposited directly on the surface of one or more of the panes of glass. The low-E coating reduces the infrared radiation from a warm pane of glass to a cooler pane, thereby lowering the U-factor of the window. Different types of low-E coatings have been designed to allow for high solar gain, moderate solar gain, or low solar gain. A low-E coating can also reduce a window's visible transmittance unless you use one that's spectrally selective.

Window manufacturers apply low-E coatings in either soft or hard coats. Soft low-E coatings degrade when exposed to air and moisture, are easily damaged, and have a limited shelf life. Therefore, manufacturers carefully apply them in insulated multiple-pane windows. Hard low-E coatings, on the other hand, are more durable and can be used in add-on (retrofit) applications. The energy performance of hard-coat, low-E films is slightly poorer than that of soft-coat films.

Self-cleaning glass

Self-cleaning glass is a specific type of glass with a surface which keeps itself free of dirt and grime through natural processes. The first self-cleaning glass was based on a thin film titanium dioxide coating. The glass cleans itself in two stages.

The "photo catalytic" stage of the process breaks down the organic dirt on the glass using ultraviolet light (reflected from the glass)even on overcast days and makes the glass hydrophilic (normally glass is hydrophobic). During the following "hydrophilic" stage rain washes away the dirt, leaving almost no streaks, because hydrophilic glass spreads the water evenly over its surface.

Bullet-proof glass

Bullet-proof glass is thick, multilayer laminated glass. This glass can stop even heavy-caliber bullets at close range. Bullet-resisting glass is heavy enough to absorb the energy of the bullet, and the several plastic layers hold the shattered fragments together. Such glass is used in bank teller windows and in windshields for military tanks, aircraft, and special automobiles.

Body-tinted glass

Body-tinted glass is a normal float-clear glass into whose melt colorants are added for tinting and solar-radiation absorption properties. This reduces heat penetration in buildings. Coloured glass is an important architectural element for the exterior appearance of façades. Body-tinted Glass is also used in interior decoration.

Production is the same as in float glass production. The only variation is the colorants mixed at the beginning with the standard raw materials. Different additives may produce differently colored glasses.

Sand Blasted Glass

This is produced by spraying sand at high velocities over the surface of the glass. This gives the glass a translucent surface, which is usually rougher than that obtained by etching. During sandblasting, only the areas that are to remain transparent are masked for protection. The depth and degree of the translucency of the sand-blasted finishing vary with the force and type of sand used. Sand-blasted glass can be used in numerous interior design applications in both residential and commercial settings: doors, shower screens, partitions and interior screens, furniture, etc.

Acid-etched Glass

It is produced by acid etching one side of float glass. Acid-etched glass has a distinctive, uniformly smooth and satin-like appearance. Acid-etched glass admits light while providing softening and vision control. It can be used in both residential and commercial settings (doors, shower screens, furniture, wall paneling, etc.).

Wire glass

Wired glass is a product in which a wire mesh has been inserted during production. It has an impact resistance similar to that of normal glass, but in case of breakage, the mesh retains the pieces of glass. This product is traditionally accepted as low-cost fire glass. In the production of wire glass, a steel wire mesh is sandwiched between two separate ribbons of semi-molten glass, and then passed through a pair of metal rollers which squeeze the "sandwich of glass and wire" together.

Stained glass

The term stained glass can refer to the material of colored glass or the craft of working with it. Although traditionally made in flat panels and used as windows, the creations of modern stained glass artists also include three-dimensional structures and sculpture.

"Stained glass" has been applied almost exclusively to the windows of churches, cathedrals, chapels, and other significant buildings.

Fiber glass

Fiberglass, (also called fibreglass and glass fiber), is material made from extremely fine fibers of glass. It is used as a reinforcing agent for many polymer products; the resulting composite material, properly known as fiber-reinforced polymer (FRP) or glass-reinforced plastic (GRP), is called "fiberglass" in popular usage.

Bent Glass

This is a normal glass that is curved with a special process. It can be used for external sites such as facades, shop fronts and panoramic lifts. This glass is also commonly used for internal sites for showcases, shower doors and refrigerator cabinets

Patterned Glass

This glass does not have a perfectly-smooth surface but rather has different patterns impressed on it. The most common method for producing patterned glass is to pass heated glass (usually just after it exits the furnace where it is made) between rollers whose surfaces contain the negative relief of the desired pattern(s). The depth, size and shape of the patterns largely determine the magnitude and direction of reflection. Patterned glass usually transmits only slightly less light than clear glass. It can be used for a variety of applications such as interior design and decorations, furniture, windows and street furniture.

Enamelled Glass

This is tempered or heat-strengthened glass, one face of which is covered, either partially or totally, with mineral pigments. In addition to its decorative function, enameled glass is also a solar ray controller. Enamelled glass is used for glazing and for cladding facades and roofs. It can be assembled into laminated glass or glazed insulation

Colored structural glass is a heavy plate glass, available in many colors. It is used in buildings as an exterior facing, and for interior walls, partitions, and tabletops.

Soda Glass

Soda Glass is the cheapest & most common glass. It is prepared by fusing soda ash, sand, limestone. It is also called soft glass. It fuses at comparatively low temperatures. The major disadvantage of using this glass is that it is brittle & breaks easily. It cracks when subjected to sudden changes of temperature. Soda glass is used for the manufacture of window glass, glass mirrors, common glassware etc. it is easily attacked by chemicals.

Hard Glass

Hard Glass is obtained by fusing potassium carbonate & limestone. It is used for making hard glass apparatus. It is more resistant to the action of acids.

Lead Crystal Glass

Lead Crystal Glass is made from potassium carbonate, lead oxide & sand. Lead glass has high refractive index. It, therefore, sparkles & is used for making expensive glass ware. The surface of lead glass objects is often cut into decorative patterns to reflect light. Cut glass show extraordinary sparkle.

Pyrex Glass

It is made by fusing a mixture of sand, lime, borax (Na2B4O7.10H2O) & alkali carbonates. It has good chemical laboratory apparatus, ampoules, pharmaceutical containers, etc. In home, it is familiar with oven ware.

Optical Glass

It is specially made so as to be free of strains & defects. It is used for making lenses for spectacles, microscopes, cameras, telescopes & other optical instruments.

Colored Structural Glass

Colored structural glass is a heavy plate glass, available in many colors. It is used in buildings as an exterior facing, and for interior walls, partitions, and tabletops.

Opal glass

Opal glass has small particles in the body of the glass that disperse the light passing through it, making the glass appear milky. The ingredients necessary to produce opal glass include fluorides (chemical compounds containing fluorine). This glass is widely used in lighting fixtures and for tableware.

Foam glass

Foam glass, when it is cut, looks like a black honeycomb. It is filled with many tiny cells of gas. Each cell is surrounded and sealed off from the others by thin walls of glass. Foam glass is so light that it floats on water. It is widely used as a heat insulator in buildings, on steam pipes, and on chemical equipment. Foam glass can be cut into various shapes with a saw.

Photochromic glass

Photochromic glass darkens when exposed to ultraviolet rays and clears up when the rays are removed. Photochromic glass is used for windows, sunglasses, and instrument controls.