Textbook Makers: A History of American Studio Craft by Janet Koplos and Bruce Metcalf
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Glossary of Glass Terms

For the purpose of general reference, the scope of these glossaries extends beyond terms used in the textbook. Other Glossaries: Ceramic Fiber Glass Metal Wood

Scroll down or select a first letter range: <a-f> <g-m> <n-s> <t-z>

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Annealing oven/annealer
a special oven which gradually reduces its temperature to cool glass after it is blown, preventing the glass from breaking or cracking from being cooled too quickly Return to Top
Batch
the ingredients placed in the furnace which melt into glass, usually formed of natural substances such as sand and silicates Return to Top
Bench
a bench with steel arms which the blowpipe is rolled back and forth, keeping molten glass on the center Return to Top
Blank
pieces blown and annealed for later decoration using either hot or cold techniques; this can refer to either Graal or overlay work Return to Top
Blowpipe
a long hollow steel tube used for blowing glass Return to Top
Bubble
air or gas filled cavity in glass Return to Top
Cameo/Intaglio
a technique in which the finished glass form is covered with another coating of glass of a different color into which is carved or etched a design which exposes the base color Return to Top
Cased glass/casing
glass completely covered (through blowing or by dripping) by other, usually different colored, glass; outer layers can be partially cut away to reveal colors of the previous “castings” beneath Return to Top
Cold work/cold-fabricated
general term for glass making processes not involving heat or the molten state, including engraving, etching, cutting, sandblasting, polishing, or grinding. Return to Top
Color
colored glass in powder, frit, or solid rod form to introduce color to clear glass which contains oxides and metals that may react during reheating and cooling; each batch is carefully tested to ensure compatibility with clear glass and each color Return to Top
Copper foil technique
joining glass by applying adhesive copper tape to each piece and soldering the copper together Return to Top
Craquelle
textured ice glass Return to Top
Crucible
container of heat resistant material to hold molten glass in furnace Return to Top
Cullet
chunks of glass, often recycled from other batches or broken glass, melted in the furnace for the artist to use Return to Top
Cutting
the process of cutting glass into pieces Return to Top
Dichroic glass
glass containing multiple micro-layers of metal oxides which give the glass dichroic optical properties. Return to Top
Enameled glass
decorated with particles of translucent, usually colored, glass or glass-like material, which fuses to the surface under heat (may be multi-colored or monochrome in design) Return to Top
Etching
a process in which acid is used to cut into the glass plate, creating intricate designs in relief on the glass Return to Top
Filet-de-verre
French term for glass threads Return to Top
Flamework/Lampwork
the technique of manipulating glass by heating it with a small flame Return to Top
Float glass
glass poured into a “river” in a long factory, and then cut into sheets Return to Top
Flocked glass
glass which has been been coated with a fiber that creates a textured surface, often associated with kitsch objects Return to Top
Foot
design element on the bottom of a piece to elevate; usually applied in molten state and shaped using tools Return to Top
Free blown
glassware shaped by air-pressure, such as mouth blowing through a metal “pipe” to which molten glass adheres Return to Top
Fumed glass
glass with an iridescent surface Return to Top
Furnace
an oven used to heat glass to its melting point Return to Top
Fuse
to bond two or more pieces of glass together by heating in a kiln Return to Top
Gaffer
the lead glassblower in a glassblowing team, who makes all the fine design decisions on a piece Return to Top
Gather
a blob of molten glass on the end of the blow pipe, the process of accumulating glass on the end of the blowpipe by turning the blowpipe in the hot batch in the furnace Return to Top
Glassblowing
process of shaping a gather of glass by blowing air through a blowpipe; the piece may be reheated and blown repeatedly to change its form and size Return to Top
Glory hole
a smaller furnace, kept hot during the glassblowing process, for the gaffer to reheat glass as it is being blown and worked Return to Top
Graal technique
a technique in which the glass is blown twice; glass is made with a color overlay which is then cut, etched or sandblasted with a decoration, the piece is then subjected again to the furnace to impart fluidity and smoothness to the design and then encased in lead crystal Return to Top
Grinding
a process in which glass is ground down to create shapes or edges; the step in the process often preceding polishing Return to Top
Hot glass
a term used to describe glass that is worked in its molten state, usually in three dimensions; it is used in opposition to “stained glass” which is usually flat worked cold Return to Top
Hot shop
term for the space and equipment required for blowing glass Return to Top
Incalmo
the process of joining different blown glass bulbs while still on the blowpipe then shaping them into the desired form Return to Top
Jack
steel or wooden pinchers used to aid in transfer of work Return to Top
Lampwork/Flamework
the technique of manipulating glass by heating it with a small flame Return to Top
Leaded glass
glass containing a percentage of lead oxide, which increases its density and improves its ability to refract and disperse light; it is used in ornaments, decorative and luxury tableware Return to Top
Lehr
annealing oven Return to Top
Luster
a type of glazing, formed with metallic oxides, creating an iridescent effect on the surface Return to Top
Marver table
a steel table used to cool a hot gather of glass by rolling it back and forth Return to Top
Millefiori
from the Italian thousands of flowers, glass cane patterns with images of flowers Return to Top
Mold
a negative model of an object, into which glass (or clay or metal) can be poured to assume its shape Return to Top
Multiform glass
similar to pâte de verre, an experimental form of glass that Harvey Littleton discovered when his father worked at the Corning factory as a physicist Return to Top
Murrine
Italian term for cross-sections of fused glass cane, often bearing a pattern or image Return to Top
Off-hand blown glass
that which is shaped and finished by blowing and with hand tools rather than by using molds Return to Top
Overlay
the technique of inverting a bubble of clear and colored glass over another bubble; primarily used in Graal technique or overlay blank Return to Top
Pâte de verre
a technique for making glass in which glass paste is pushed into a mold, heated, and removed from the mold once the glass assumes its shape Return to Top
Plate glass
glass which is heated, poured onto a surface, rolled thin, and cut into “plates”, often used for industrial purposes Return to Top
Polishing
a necessary step in the glassblowing process, which smoothes any sharp edges and adds luster to the glass surface Return to Top
Pontil
a solid steel rod used to gather molten glass or to transfer blown work to allow gaffer to open and change form of the mouth of the vessel Return to Top
Puffer
a smaller form of the blowpipe, used to further shape the blown glass form after it has been blown Return to Top
Sand-blasted glass
glass whose surface is blown with fine sand under high pressure, it results in a roughened, non-transparent surface; decorative patterns can also be produced by using protective stencils Return to Top
Slumping
a process of melting glass just enough that it assumes the form of the object on which it is placed Return to Top
Soda-lime crystal
a type of glass not particularly resistant to heat and used in windows and bottles Return to Top
Studio glass
glass designed and made by an artist/craftsperson rather than factory made glass Return to Top
Surface decoration
many chemicals and physical substances are applied to hot glass during the blowing process, often by rolling the hot glass over a table where the substance has been sprinkled; commonly used are powdered or crushed glass, and silver nitrate Return to Top
Tesserae
the individual tiles in a mosaic Return to Top
Trail
to apply a coil or bullet of glass to the surface of a piece in progress Return to Top
Ventilation hood
a piece or equipment that eliminates hear and dangerous fumes while circulating fresh air to keep the gaffer safe and cool while working with molten glass Return to Top
Vitreography
printmaking using glass plates Return to Top