Glossary of Stained Glass Terms

Acid Etching: use of hydrofluoric acid to dissolve the surface of the glass; this is used often on FLASHED GLASS to remove a layer of color, revealing the base layer of glass.

Antique Glass: mouth-blown glass, made by the muff method, in which a tube of glass is blown, then split lengthwise and opened to create a rectangular sheet.

Armature: steel or iron framing member within the window opening which supports stained glass panels.

Buckle and bowing: descriptions for condition of lead came matrix, seen when saddle bars and structural support fails, windows appear to ‘sag’

Badger, Badgering: 1. wide, flat brush made of badger hair, used for blending MATTE PAINT; also called a blender; 2. the process of blending a MATTE using a badger brush.

Blender, Blending: see BADGER

Bull’s Eye: the raised center portion of a glass CROWN, from which the PONTIL was detached.

Came: extruded, cast, or milled H-profile metal strip, usually made of lead, sometimes of zinc, copper, or brass, used to hold pieces of glass together to make a stained glass window (archaic: CALME, CALM).

Cartoon: full-size drawing for a window.

Carving: using SANDBLASTING to create areas of varying depth on plate glass to simulate three-dimensional surfaces.

Casement: a window which opens on a vertical pivot at the edge of the SASH.

Cathedral Glass: machine-rolled clear or colored glass.

Cement: liquid waterproofing compound.

Channel: U-profile metal strip made of lead, zinc, copper or brass, usually used to frame PLATES or autonomous PANELS.

Cold Paint: any unfired paint used to decorate stained glass.

Confetti Glass: glass in which chips of glass of other colors are incorporated.

Copper Foil: thin, narrow strip of copper, usually with adhesive backing, used to join pieces of glass.

Core: see HEART

Crown Glass: hand-blown glass made by blowing a globe, which is then opened at the base and spun, forming a circular sheet of glass with a BULL’S EYE at its center.

Double-Hung: windows where the SASH slide vertically in their FRAMES.

Drapery Glass: OPALESCENT glass which is manipulated during its manufacture to form similar in appearance to cloth.

Dutchman: see MENDING LEAD.

Enamel: opaque, colored glass paint made essentially of powdered, colored glass.

Etching: decoration on glass, made by:  1. SANDBLASTING, or with 2. ACID.

Favrile Glass: trademark of the Tiffany Studios: glass is highly iridized, design for use predominantly in glass objects and vessels; term is used erroneously to describe iridized glass in stained glass windows.

Fillet: narrow border(s).

Fire, Firing: process of placing newly painted glass in a kiln to heat it to a temperature at which the glass paint melts and fuses to the surface of the glass.

Flange: in a CAME, the parallel legs of the H-profile. (See MENDING LEAD)

Flash(ed) Glass: colored ANTIQUE GLASS in which a pale-coloured or clear base layer is coated during blowing with a thin layer of darker color.

Frame: supporting elements for PANELS or SASH, which encompass a window opening.

Glass: a mixture of silica (sand), ash, soda, lime and colourants, which are melted, then cooled into a non-crystalline, inorganic super-cooled liquid.

Glass Paint: see COLD PAINT, ENAMEL, GRISAILLE, SILVER STAIN, VITREOUS PAINT; any of a number of materials used to decorate glass; it does not impart color to the body of the glass.

Glaze, Glazing: 1. process of installing glass or windows; 2. process of assembling leaded glass panels; 3. windows.

Glazier: 1. one who installs leaded glass panels or windows; 2.  one who installs glass into FRAMES or SASH.

Grisaille: (French, grey) 1. Black, brown, grey, or other dark-colored VITREOUS PAINT, used to decorate glass; 2. Windows of clear glass decorated primarily with this paint, using little or no coloured glass.

Groze, Grozing: process of modifying shapes of glass pieces by chipping away the edges, using either grozing pliers, grozers, the notched side of a glass cutter, or, archaically, a notched iron rod.

Heart: center of came: the bar of the H-profile.

Jewel: cast or chipped faceted glass pieces.

Lancet: narrow vertical divisions of a window having a pointed Gothic arch at the top, used singly or in multiples for form a larger Gothic window.

Lead: soft, malleable metal used in came.

Lead Line: 1. in window design, line which indicates placement of came; 2. pattern of caming in a window.

Leading-Up: process of GLAZING, or assembly of leaded glass panel.

Light: glass-filled opening between MULLIONS of a window.

Light Leaks: gaps between glass and lead, or panel and frame, through which
daylight can be seen.

Lunette: semi-circular window.

Matte Paint, Matting: 1. washes of GLASS PAINT, usually GRISAILLE, usually applied to the interior surface of the glass; used for shading; 2. process of applying washes of GLASS PAINT.

Mending Lead (also DUTCHMAN, FLANGE, or STRAP LEAD): full came or flange of came (separated from the heart of the came) inserted between broken pieces or applied to the surface of the broken pieces

or applied to the surface of the broken piece of glass.

Mullion: FRAME member, usually vertical, dividing frame into LIGHTS.

Oculus: circular window, not divided by spokes or radil.

Opalescent Glass: milky, opaque glass, often of more than one color, developed in late 19th century American and popularized by Louis Comfort Tiffany.

Panel: unit of leaded glass.

Patina: 1. surface film produce by chemical action of air pollutants, dirt, and water on glass over the course of time; 2. chemicals applied to glass, came, or copper foil to induce the appearance of aging.

Plate, Plating: layered piece(s) of glass.

Pontil (or Punty): iron rod to which blown globe of hot glass is attached to spin a CROWN.

Putty: thick waterproofing or setting compound.

Quarry: regular geometric shapes of glass, used in a repeating design.

Rose Window (also Wheel Window): circular window divided by radial mullions, usually in a floral or wheel pattern.

Roundel (or Rondel): round clear panel, composed of a single piece of glass, (see bullseye) sometimes with borders, painted with a complete scene, usually in GRISAILLE and SILVER STAIN.

Saddle Bars: round or flat, iron or steel support bars, which are set into the SASH or FRAME, crossing the window opening, usually on the inside of the stained glass panel, to which the stained glass is fixed with TIE Wires, to prevent bowing and sagging.

Sandblasting: process in which sand under very high pressure is directed at glass covered with a STENCIL; those areas not covered by the stencil are etched or frosted.

Sash: the operable or removable part of a window.

Seeds: small bubbles in ANTIQUE GLASS

Silver Stain: a type of GLASS PAINT composed of silver nitrate or silver chloride, applied to the exterior surface of glass; when fired, it stains the glass a yellow to golden-orange color.

Solder: mixture of lead and tin, melted with a soldering iron to join the ends of came or the seams of copper foil.

Spring Line: the point in an arch at which the arch begins.

Stained Glass: 1.  leaded glass PANELS; 2.  painted glass, or painted glass PANELS; 3.  glass coloured during its manufacture.

Stenciling: creation of repeated designs by painting or etching, using a cutout pattern.

Stippling: type of MATTE in which the tips of a BADGER are repeatedly touched to wet GLASS PAINT.

Stopgap: repair-using materials foreign to the window, such as glass from another, wood, lead, tar, etc.

Strap Lead: see MENDING LEAD.

Support Bars: see SADDLE BARS, T-BARS.

T-Bars: iron, steel or aluminum support bars having a T-profile, set into the FRAME and upon which the PANELS are set.

Tie Wires: copper wires or lead strips soldered to the stained glass PANELS to be wrapped around saddle bars and twisted closed.

Trace, Trace-Line: dark, opaque paint line, usually applied to the interior surface, used to delineate details.

Tracery: ornamental framework at the top of a window opening, usually one of the Gothic style.

Vitreous Paint: paint composed of ground glass and metallic oxide pigments, applied to glass for detailing and enhancement, fired in a kiln to melt and fuse with the surface of the glass.

Zinc: stiff, brittle metal used for CAME; not as common as lead came.

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Eve Guinan Design – Restoration
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