Black enamel paint Black enamel was made from ground glass plus iron filings. It was used to create the details on the earliest stained glass. It could be applied thick and black, or as a thin grey or grey-brown wash. See also: Enamels (below) Illustration: Notre Dame Cathedral, Paris France

Came, lead came A slender, grooved lead bar used to hold together the panes in stained glass or lattice windows. Extruded pure lead that is milled to specific dimensions as either "U" or "H" shaped strips, then cut and formed to accept and hold the stained glass shape.  It's available in spools or precut lengths of about 6 feet. Later, zinc, copper, brass, etc. were substituted for the lead. See also, Stained Glass Resources, Restoration of Stained Glass Windows: What is Releading? Illustration: Comtemporary catalog

Cartoon / drawing / Sketch A design or study drawn of the full size, to serve as a model for transferring or copying - used in the making of stained glass windows, mosaics, tapestries, fresco pantings, etc. The line drawing for a work of glass with all cut lines shown. Individual pieces may be numbered and color shadings indicated. A second copy is cut for pattern pieces. See also, Stained Glass Resources, The Sketch Illustration: Courtesy of Jack Edson Joseph Mazur Stained Glass Cartoon

Cathedral Glass Transparent, colored glass - generally in a single color - machine made to uniform 1/8 thickness and either smooth or with a choice of textures. Although machine made, the name comes from its resemblance to stained glass first used in Medieval European cathedrals. Contrast to pot metal glass below and to opalescent glass below.

Catspaw A surface texture resulting from the chilling of hot glass on a cool table. The appearance is likened to the paw prints of a cat. Catpaw Glass appears as though a cat has walked across its surface and left paw prints. Transparent and available in many colors, it is often used for backgrounds or special effects. For an explanation of how modern cats paw glass is made, see Kokomo Opalescent Glass: Tour the Factory - The Catspaw Table Illustration: Art Nouveau style transom window detail, Carl Slone

Cement A cementing compound is brushed under the edge of all the lead to fill in any space between the lead and the glass.  The front side of the window is cemented first and allowed to cure; then the backside is cemented.

Drapery glass Glass sheets with multiple dramatic folds, likened to those in hanging drapes. Refers to a sheet of heavily folded glass that suggests fabric folds. A small diameter hand-held roller is manipulated forcefully over a sheet of molten glass to produce heavy ripples, while folding and creasing the entire sheet. The ripples become rigid and permanent as the glass cools. Tiffany made adundant 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. - Wilipedia: Tiffany glass: Drapery glass

Enamels There are four primary ways to color glass: Pot metal Flashing Staining Enameling Enmels are soft powdered colored glass that is mixed with a medium and painted onto the glass with a brush.  When the medium is dry, the glass is placed in a kiln for firing. The Romans mixed the powdered glass with oil until it has the consistency of paint. In the Gothic era, black enamel was made from ground glass plus iron filings. The Romans also cold-painted, i.e., did not refire the glass after it was enameled. See Black enamel paint (above) Another coloring method, discovered in the sixteenth century uses enamels. Enamels arc compounds of ground glass and oxides that become fairly transparent when heated and fused to clear or white glass. Entire scenes can be painted in colored enamels on a single piece of glass. As the use of enamels became more widespread (during the seventeenth and eight-teenth centuries) all the old methods of coloring glass - pot metal, flashing, and staining - were nearly lost. Colored enamels seldom have the brilliance of pot-metal glass but can take on a rich translucence when enamels are carefully applied. Enameling fell out of favor in the late-nineteenth century as interest in the ancient stained glass techniques rekindled. - Nola Huse Tutag, Discovering Stained Glass in Detroit. Wayne State U. Press, 1987, pp. 9-10. Illustration: Christ with Children - Detail, Corpus Christi RC Church

Etching Method of removing one layer of color from flashed glass in a hydrofluoric acid bath.  The glass to be etched is exposed via cutting a stencil from a completely covered piece of glass.  Hydrofluoric acid is the only liquid material that will dissolve silica - the main ingredient in glass.  The length of exposure to this corrosive acid will determine how far the acid will eat into the glass.

Faceted / Dalle-de-verre / Dalle / Slab glass Large faceted glass pieces arranged mosaic-style in concrete or epoxy. "Process: A twentieth-century innovation in the art of stained glass introduced the use of glass dalles measuring approximately 8"x 12"x 1". These dalles, cast in hundreds of colors, can be cut into shapes and used, in combination with an opaque matrix of epoxy resin 5/8"to 7/8" in thickness, to create translucent (below) windows and walls of great beauty." - Stained Glass Association of America Faceted glass is constructed of 1" thick chunk stained glass, cut to shape and then cast in an epoxy resin. The result is a very heavy and durable window panel.  "Slab glass" is chipped on the edges to cause thin flakes of glass to break off the flat surfaces.  Pieces of this type of glass are set into an epoxy-concrete mixture to produce large architectural window-walls. The fractured edges ("facets") cause the light to bend and refract (break into a rainbow of colors).

Favrile glass Tiffanyís signature Favrile glass, distinguished by its deeply toned, rich colors and often brilliant, iridescent finish. Trademarked in 1894, Favrile glass (the name is derived from the old English ìfabrileî meaning ìhand-wroughtî) quickly became fashionable and inspired many other designers. Favrile glass often has a distinctive characteristic that is common in some glass from Classical antiquity: it possesses a superficial iridescence (below). 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.

Flashed glass There are four primary ways to color glass: Pot metal Flashing Staining Enameling Flashed glass is one sheet of glass made of two layers of color.  Any color can be flashed on top of another. Made by dipping a ball of semi-molten white ("colorless") glass into molten colored glass which, when blown and flattened, results in a less intense color because it will be white on one side and colored on the other. In the Gothic era, natural pot-metal (above) glass colored blue or red was too dark to transmit much light, so the medieval glazier (above) hit on the technique of flashing. A semi-molten cylinder of colorless ("white") glass was dipped into a pot of red glass so that the red glass formed a thin coating. This allowed a variety in the depth of red, ranging from very dark and almost opaque, through ruby red to pale, and sometimes streaky red that was often used for thin border pieces. The red of double-layered glass could be engraved or scraped to show colorless glass underneath. In the late medieval glass this method was often employed to add rich patterns to the robes of saints. You can easily tell a piece of flashed glass by scratching at a corner with a glass cutter or just chipping a small bit away. The underlying color will show through.

Fracture glass "Fracture glass refers to a sheet of glass with a pattern of irregularly shaped, thin glass wafers affixed to its surface. Tiffany made use of such textured glass to represent, for example, foliage seen from a distance." - Wikipedia: Tiffany glass

Fusing  The technique of controlled melting of combinations of glass in layers using a kiln.

Glass Glass is a hard material with non-crystalline, random structure like a liquid. It is commonly made by combining materials such as silica, potash, and lead oxide at a high temperature in order to allow the materials to melt and fuse together. When cooled rapidly, the substance becomes rigid . Glass is often classified as a supercooled liquid rather than a regular solid. Glass is made with very basic ingredients. Sand is the main ingredient, and then added to that are ashes from trees or plants which help the sand to melt. Something like lime is also added which is a stabilizing ingredient, and it protects the glass from moisture. Virtually the same recipe is used to make glass today, but through the years there have been many variations, and new recipes continue to emerge.

Glassblowing The art of shaping a mass of glass that has been softened by heat by blowing air into it through a tube. 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. His reheating furnace is called a "glory hole" (above). The discovery of glassblowing was made somewhere around the year 50 BC.by the Romans. Most early stained glass was made by mouth-blowing long cylinders of molten glass, which were partly cooled, had the ends removed, were cut open, reheated and flattened. See pot metal below. Illustration: 1 of 8 Imges of Glassblowing at the Corning Museum of Glass

Glazier One that cuts and fits glass

Glory hole Gaffer's (above) reheating furnace. Name is a tribute to the beauty the gaffer creates.

Grisaille (gri ZEYE, ZAIL) Deecorative work or illustrative scenes rendered mainly in shades of grey (or muted brown) Grisaille is the use of black enamel to create patterns on clear glass. A kind of paint able to be fired onto glass. Silvery tinted glass with floral patterns that replaced stained glass. Grisaille is a lacy pattern painted on light glass with vitrifiable paint (able to be fired and turned into glass) and fired. Toward the end of the thirteenth century a desire for more illumination surfaced with an increase in nonfigurative windows and concentric patterning that incorporated more transparent glass. Grisaille glazing was first favored by the Cistercian Order under St. Bernard, who found that figurative windows distracted monks from religious responsibilities. In English 15th-century illustration, grisaille was often used in combination with colours or gold, i.e., figures in a monochrome tone against a coloured background. As the palette became increasingly lighter, horizontal layers of colored glass and grisaille, or band windows, were incorporated in the figurative windows. Grisaille became increasingly common throughout England and France until it all but replaced stained glass in what little was left of the market in the seventeenth and eighteenth centuries. See also: The Stained Glass Association of America: History of Stained Glass: Gothic Stained Glass Illustration: St. Andrew's Episcopal Church - Buffalo Nave windows St. Andrew's Episcopal Church - Buffalo Narthex window, St. Andrew's Episcopal Church - Buffalo Holy Family Shrine and Lady Chapel window, St. Andrew's Episcopal Church - Buffalo Trinity (Episcopal) Church - New York City

Iridescent Not a surface texture, but a special surface finish.  Finish produces a metallic sheen creating a colorful, shimmering effect\, a rainbow effect.  Glass with a colorful shimmering effect created when a layer of metallic oxide is bonded to hot glass. Illustration:Sconce, Barton House

Jewel Piece of hot glass that is press-molded into a jewel like shape. Cathedral or opalescent glass that has been pressed into steel molds and then polished for consistent shapes and sizes.  Facetted round, navettes and square shapes; smooth ovals and rounds, raised swirls and "iceberg" shapes are just a few of the types of jewels available. Illustration: St. Paul Episcopal Cathedral Eastlake style transom - Detail

Kokomo Opalescent Glass Works The Opalescent Glass Works at Kokomo, Indiana is the oldest manufactory (since 1888) of its kind in America. "Louis Heidt had been under long-term contract with Tiffany since 1881 ... An early production journal in the archives of KOGC documents that the first order was made on Nov. 16, 1888 for Tiffany Glass Co.; six cases (600 lbs.) of mixed blue/white opalescent glass. Scrutiny of journal entries for the first months of production reveals that Henry began making glass in Kokomo with at least 93 separate stock color combinations already in his repertoire, including gold ruby, ripple and drapery glass, all offered in a variety of densities. His biggest customers during this start-up period were Tiffany, Decorative Stained Glass (LaFarge), George Androvette, McCully & Miles and Flanagan & Biedenweg - in short, many of the most respected studios in the country." - KOGC Website The modern method of producing stained glass is by ladling molton glass onto a table and then into a roller. See the process in photos with captions: Kokomo Opalescent Glass: Tour the Factory Illustration: Kokomo Glass website

Kiln A chamber made of firebrick in which to bend or fuse glass.  Size ranges from small tabletop units to 3' x 4' bed, floor models.  They can be electric or gas heated.

Medallion or Narrative windows In Gothic chuches, medallions in nave windows depicted scenes from the Old and New Testaments. Illustration: Westminster Presbyterian Church

Metal Colored glass, known as "metal" was made by adding various metallic oxides to the crucibles ("pots") in which the glass was melted. This is the basic stained glass of a single colour. See pot metal below.

Molton glass Photo: Kokomo Opalescent Glass

Mottled, Ring mottled Glass with areas of opaque and translucent spots of color. May be one, two or three colors per sheet. Well suited to organic and three-dimensional imagery. Dappled: having spots or patches of color Patterned with spots or blotches. Appearance of uneven colour Spots of lighter and deeper shades Glass that has variation in coloration in the form of small spots, some of which run together. Mottle or mottling is the appearance of uneven spots on plants or the skin of animals. In plants, mottling usually consists of yellowish spots on plants, and is usually a symptom of disease or malnutrition Traditional mottled glasses impart an orangish gray cast to the glass. CATSPAW above RING MOTTLE GLASS 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.

Opalescent glass

Opaque glass Neither reflecting nor emitting light; allowing little or no light to pass through. Not translucent (letting only some light through, so that objects on the other side appear blurry). Opposite of transparent (see through)

Painted glass From the fourteenth century in Italy, translucent oil paint ["enamels"] was painted onto stained glass to enrich the range and quality of colors. See Enamels above.

Pictorial windows Depicting historical scenes that were scattered over a window ignoring the window support lines. See also Munich Pictorial Style Stained Glass Windows in Buffalo Illustration: St. Paul Episcopal Cathedral

Plating Sometimes glass is more than one layer thick, meaning another piece of glass may be mounted in front of, or behind another, which requires additional glass and modified construction techniques.

Pontil, punty A solid metal rod used, tipped with a wad or ring of hot glass, to remove a blown object from the blowpipe in order to allow the top to be finished and any other final shaping to be done. Pontil mark When the glass has cooled and solidified it is knocked off the rod, leaving a rough mark, the 'pntil mark'. Refers to the place on the base of a glass object where it is attached to the punty rod or pontil while the blower is shaping and finishing the piece, and then snapped off and polished smooth.

Pot metal glass ("Antique glass") There are four primary ways to color glass: Pot metal Flashing Staining Enameling Pot metal is glass that is of one solid color, no texture and extremely opaque with no light transmitted.  Two examples are solid, dense white and black. In medieval times, to lighten the color, flashing was used. The medieval name for the molten glass batch.  It was heated in a large crucible and metallic oxides were added for color. Colored glass, known as "metal" was made by adding various metallic oxides to the crucibles ("pots") in which the glass was melted. This is the basic stained glass of a single color. Sheet glass can be made by the centuries old method of mouth blowing.  The glass is blown into cylinders.  The closed end of the cylinder is cut off and the side cut to flatten into a sheet. The modern method of producing stained glass is by ladling molton glass onto a table and then into a roller. See the process in photos with captions: Kokomo Opalescent Glass: Tour the Factory Pot metal (Antique glass) Sand, soda and lime are fused together in a pot, or crucible at a very high temperature, at which time chemicals, metals or metalic oxides are added to the molten mixture to produce a full range of colors. The product is known as "pot metal" or "pot metal glass." The glass blower gathers up the required amount of molten metal on his long rotating pipe and blows a bubble or blows the shape in a mold. The ends are cut off the bubble and the sides of the resulting cylinder are split. Oven treatment produces flat sheets approximately 15"x17". Contemporary glass produced in this manner is called "antique glass."  Variation in color and thickness even within a single sheet of glass  contribute to the infinite possibilities available to the creative team. - Stained Glass Artwork Photo, modern "pot" - Kokomo Opalescent Glass website

Ripple glass Texture that has the appearance of ripples that is applied to hot glass sheets with an embossed roller Sheet of textured glass with marked surface waves. Louis Comfort Tiffany made use of such textured glass to represent, for example, water or leaf veins. Illustration: Art Nouveau style transom window detail, Carl Slone

Roundel (RON dle) A mouth-blown piece of glass that has been spun into a circular shape, often irregular. Sometimes incorporated into leaded glass artworks. Machine-made facsimiles are common, called "pressed rondels."

Rose window Illustration: Sainte Chapelle, Paris, France

Saddle bars The round support bars on a stained glass window. They are attached to a stained glass panel with copper wire that has been soldered on to lead joints (where one piece of lead meets another) and then the ends are twisted firmly behind the bar to hold the panel in place. The flat support bars are called fins. They should be soldered directly to the stained glass panel at all possible lead joints. Both saddle bars and fins should be attached to the sash as well as the panel, otherwise, it's just a piece of metal attached to the window, not supporting it. Booklet available for purchase: Stained Glass Association of America, "Standards and Guidelines for the Preservation of Historic Stained Glass" Illustration:

Silkscreening A printing method of applying paint to glass where the paint is forced through a fine mesh (screen) overlying a stencil. Paint is deposited in the open areas of the stencil. Illustration: Detail - Asbury Delaware Methodist Church / Babeville.... .Complete window

Stained glass "As a material stained glass is glass that has been coloured by adding metallic salts during its manufacture. The coloured glass is crafted into stained glass windows in which small pieces of glass are arranged to form patterns or pictures, held together (traditionally) by strips of lead [came] and supported by a rigid frame. Painted details and yellow stain are often used to enhance the design. The term stained glass is also applied to windows in which the colours have been painted onto the glass and then fused to the glass in a kiln." - Wikipedia Process of designing and fabricating stained glass 1. Paint watercolor 2. Draw/paint cartoon. 3.Cut glass. Some pieces are then left as they are, others have additional artwork. 4. Paint details on glass and then refire glass. Using a kiln, the stained pieces of glass are then placed for several hours in a kiln, where the stain becomes permanent and part of the glass 5. Lead the window. To hold all the glass pieces together, a frame work of lead is used. The lead is shaped into the from of an "H" to surround each piece of glass.  6. Solder 7. Assemble glass in frame and install Theophilus Techniques of stained glass window construction were described by the monk Theophilus who wrote a how to for craftsmen about 1100 AD. It describes methods little changed over 900 years: "... if you want to assemble simple windows, first mark out the dimensions of their length and breadth on a wooden board, then draw scroll work or anything else that pleases you, and select colors that are to be put in. Cut the glass and fit the pieces together with the grozing iron. Enclose them with lead cames ..... and solder on both sides. Surround it with a wooden frame strengthened with nails and set it up in the place where you wish." The Stained Glass Process at the Community Methodist Episcopal Church of Jackson Heights The subject of our windows were probably selected by Dr. Moore and approved by a church committee and the most generous potential donors. The Payne-Spiers studio of Paterson, New Jersey was commisioned to produce a small, scale design incorporating these subjects. Once approved, a full scale design, would probably have been executed in watercolor to simulate somewhat the translucence of light. This design would be translated into full-size working drawing, the "cartoon," showing the exact dimensions of the completed window. A tracing ["pattern"] from the cartoon is cut up to make templates for each piece of glass, minus the shapes are cut and filled, reassembled by the glazier on a large piece of clear glass to ascertain whether the color, tonal value and type of glass follow the original design. With light from behind, the artist now uses black or brown vitreous paint with a variety of brushes for shading, matting, stippling and line work. Silver nitrate "stain" may be used to affect the colors. To permanently fuse the paint and stain with the glass the pieces are fired in a kiln. Given the fact that stained glass windows are pictures FROM pieces of glass, the method and material of joining the pieces is an equal component in the creative process. The shaped pieces are inserted into H-shaped lead strips called "cames" and joints are soldered. The final union is "cemented" together to prevent leakage in the rain. The Process: The preparatory sketch [usually a watercolor] is translated into full-size mechanical drawings (cartoons) and further into actual patterns to be used to cut the glass. Once the patterns have been prepared and assigned color, the glass is cut into the myriad pieces required to build the window. When the design requires detail painting or ornamentation of the glass surface, it must be done with pigments designed specifically for stained glass. Once applied, the pigment is fired in a kiln to the proper temperature for the respective pigment, usually between 1000 and 1250 degrees Fahrenheit, thus assuring absolute permanency. The pieces of glass are joined together with lead came (H-shaped strips) and soldered at their inter-sections on both interior and exterior surfaces of the assembled panel of stained glass. Varying widths of lead came are often used to add to the window's decorative effect as well as enhance its strength. - Stained Glass Association of America See also: Answers.com: Stained glass

Staining / Silver staining There are four primary ways to color glass: Pot metal Flashing Staining Enameling In glassworking, staining is the process of coloring the surface of glass by the application of silver sulfide or silver chloride, which is then fired at a relatively low temperature. The silver imparts a yellow, brownish yellow, or ruby-colored stain, which can be painted, engraved, or etched. Subsequent stainings and firings can produce a deep orange. It was discovered around the beginning of the fourteenth century, apparently in France, and was used sparingly at first, and then very creatively to produce local contrasts on coloured glass.

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. - Wikipedia: Tiffany glass

Studios Studios design, fabricate, repair, and restore stained glass. To be distinguished from stained glass suppliers (e.g., Kokomo above), although sudios may work with suppliers to develop an original color, texture, etc. Studios (or designers in the studio) sometime sign their work. Illustration: Signature, St. Paul Episcopal Cathedral Examples: Burnham Connick Goodhue Guthrie Hardman LaFarge Lamb Mayer, Zettler, Tyrol, Sherer Pike Tiffany Willet Young

Translucent Glass Transmitting light but with diffusion so as to eliminate the perception of distinct images.  If you place your hand behind translucent glass, you can see its shadow but can't see any of the distinct features.  Used in panels and windows.  Almost always the primary glass used in lamps.

Watercolors Preparatory sketch in the stained glass making process. The client must approve the design, coloring, etc. before the next step is taken. Illustration: Tiffany Studios watercolor, Angels Holding Scroll and Scale, First Presbyterian Church, Lockport

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