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glossary of terms
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Technical Resources
Acid Polishing
A process whereby the gray cutting produced in glass by abrasive wheels are smoothed and polished by immersion in acid.

An ingredient added to the batch of raw material to hasten the fusion of the silica.

A decorative effect in glassware stems achieved by entrapping air bubbles in the molten glass and then stretching it into shape with a twisting motion.

The gradual cooling of hot glassware in an oven or lehr.

Glass containing, colored, opaque spangles of non-glassy material for decorative effect.

The mixture of raw ingredients ready for melting into glass.

Bench Hand
A Bench Hand works in the machine shop of the factory. They work with steel chisels, files and a hammer chipping designs in cast iron moulds.

An annealed piece of glass ready to be marked for cutting, etching or another form of decoration

Bubbles in the glass that are greater than 1/16" diameter. Usually caused by trapped gases in the molten glass batch.

A wooden tool used to symmetrically shape a gather of glass. The block is soaked in water to keep from burning and to create a cushion of steam.

Blown Glass
Glassware shaped by air pressure as by mouth blowing or by compressed air in making a article of glass.

Off-Hand Blown Glass is produced by expert mouth blowing without the aid of moulds.

Hand Blown Glass is always mouth-blown frequently into molds and completey fabricated by hand.

Machine Blown Glass is fed into molds by means of an automatic feeding device and shaped by compressed air.

Blown Molded
Glass blown into a hinged mold to give a pattern or shape.

Boric oxide gives glass a low coefficient of expansion and ability to withstand direct contact of open flame.

Bubble Glass

Glass containing many small, visible bubbles deliberately induced for decorative effect.

The over blown portion of a blown article that is removed after anneling.

Colorful pressed glass accessories marked by ornate surface decoration and bold colors. Originally produced in early 1900's


An engraved figure or design in relief, applied to a glassware piece, usually of contrasting color.

see Iridescent.


Glassware decorated by means of sand-blasting, the decorated areas taking on a soft gray color.

Glassware in which one layer of glass is applied over another. Several layers may be built up, each different in color or texture.

A wooden bench with arms on which the gaffer rolls his iron while shaping a glass object.

Chill Marks
Wave-like distortions in glassware. aka: Cold or Setteling Waves. Cause: The mould is not pre-heated enough pyor to pressing.

Cold Waves
see Chill Markes.

Thread-like lines that look like pattens of different-colored or different-textured strings wound into the item.
aka: Streaks. Cause: Variations in the glass batch and the winding pattern these variations form as the glass is wound onto the gathered puntil or blowpipe.

Cracking Off
The glass is scored by a carborundum wheel at the point where it is to be cut off. It's them placed on a rotating socket, and a sharp flame plays across the glass where the scratch was made. In a few seconds the glass will crack off along this scratch. The resulting edge is sharp and uneven and must be ground smooth and fire polished.

Glassware whose surface is marked by a network of tiny cracks deliberately induced by sudden cooling for a decorative effect.

Crack-like lines occur when the, chilled, just-formed "skin" of the pressed shape moves under pressure.

Glass melting pots, also called Monkey Pots or Skittles.

Cut-offs from the manufacturing process and rejected items are recycled and used as an ingredient in a new batch of glass.


Glass whose surface is decorated with cuttings applied by an abrasive wheel.

A glass blank is marked with lines as a guide to the cutter and cut with various wheels (iron, stone or wood) along with an abrasive agent. The wheels are large in size, 10" and above. These cuts tend to go deep and are a series of straight or slightly arched lines. The cut area is gray in appearance and more often than not the gray is polished out.

Cut Shut
A piece pressed upside sown through bottom with a collar of glass which is then warmed in and cut with shears, causing a swirled mark on base of finished piece.

Dip Mold
A one piece mold open at top for impressing a pattern.

Glass paint decoration applied to annealed piece and fired to fuse the enamel.


A decoration of precious metal, usually gold or platinum, applied by rubbing into a design already etched into the glassware piece.

Glass whose surface decoration is incised by fast-spinning copper wheels. The term "copper wheel engraving" derives from this process.

This art of Free-Hand Patterning on glass is delicate and exquisite. Executing mostly designs of crests, script monograms, Old English letters, seens of nature, and original designs.

A glass blank is cut with various wheels (typically made of copper, also iron or stone) along with an abrasive agent. The wheels are small in size, 2 to 3". These cuts tend not to go deep, but stay on the surface of the object, and include a series of loops and tight arcs. The cut area is gray in appearance and are rarely polished out.

A surface decoration on glassware resulting from acid eating into the glass in a predetermined pattern. Either of two methods may be used to apply the decoration: needle etching or plate etching.

Fire Polishing
Direct application of flame to a glassware piece to smooth it, make it glossy, or round its edges.

This is done to remove tool and or mold marks.


Clear glass is covered with a thin second layer of colored glass that can be cut through to produce various decorative effects. The result is similar to that achieved in cased glass.

see Alkai

Excess glass that is still attached to an article after molten glass is pressing into a mold. The font is cut away from the article after annealing.

Free Blown
A glass object is formed into shape without the use of a mold, by blowing and shaping using only hand tools.

Glassware made semi-opaque by a gray textured surface produced by acid bath, powdered glass fired to the surface, or sand-blasting.
A master blower, head of the shop.

A gob of molten glass on the end of a blow-pipe.

A person who performs making a gather for the gaffer is called a gatherer.

The rim of the glassware, after being properly ground and wiped clean, is glazed. A hot flame is directed down on the edges of the glass, melting the edges to make them suitable for use as drinking glasses. After glazing, the glassware is again annealed.

Glory Hole
A small furnace used for the frequent reheating needed to keep wares from hardening during shaping; also used to fire polish.

Gold Encrusted
A glass blank that has been aced etched is inlaid with 22 karat gold.

Gray Cut

A glass decoration applied by an abrasive wheel which leaves it gray and opaque. Further processing is required if a polished cutting is desired.

A grinding machine is used to grind the top edges of stemware and tumblers. Though the edges are ground smooth and flat, they're still quite sharp and require fire polishing before the item is usable.

Hokey Pokey

Hot Metal
Glass in its molten state is a metal.


Glassware with an applied coating that reflects rainbow colors when light strikes it. Metallic chloride sprayed on a still hot piece of glass causing the multi-color luster.


Lace Glass

Glass decorated with a maze of thread-like lines resembling lace fabric.

Lap Marks
Crack-like lines occur when the gathered gob of glass touches the metal of the mould before dropping into position for pressing or when a gathered gob of glass have layers of gathered glass that overlap and chill before entering the press mold or being shaped for a blowing operation.

Lead Glass
Lead Oxide combined with potash or other alkalis is used to making the glass softer, particularly adaptable for cutting.

The annealing oven for gradually cooling of hot glass objects.

Lime Glass
Glass containing a substantial proportion of lime usually processed with soda or other alkalis to produce a quick-setting brilliant glass.

Marbled Glass

Glass streaked with different colors simulating marble, produced by mixing various colored glasses with colorless or opal glass while still in the molten state.

Marvering Table

A polished metal or stone slab on which the gather is rolled while attached to a blowpipe or pontil.

Glass— either hardened or in its molten state.

Milk Glass

White opaque glass known as far back as the Egyptian civilization and before.

In the 1960's milk glass was among the most popular of all types and was offered primarily in reproductions of early decorative and serving pieces.


Decorative glass produced by fusing glass threads of different colors into a solid rod, slicing a thin disk from this rod, then encasing it in colorless glass to produce vivid floral patterns. Used primarily to decorate glass paper-weights.

Mold Mark
Lines on a glass object left by the joint of a mold.


A Muddler is used in the preparation of an Old Fashion and other cocktails. It is used to crush or "Muddle" fresh fruit at the bottom of the glass. Many glass housed made Muddlers to accompany their Lines of Barware.

Opal Glass

Colored glass with a fired-on finish that imparts a milky iridescence.


Glassware molded with a rippled or other decoration in the body for decorative effect.

A wooden tool used in the shaping of glass made of apple or cherry.

Pattern Glass

Pressed glassware originally produced in America in the half-century between about 1840 and 1890, today offered in re-productions.

The part of a mold which forces the molten glass into the contours.

Polished Cut

A glassware design cut in by an abrasive wheel and then polished either by acid or by a buffing wheel to eliminate the gray effect left by the abrasive.

A solid iron rod similar to a blowpipe, which is attached to the base of a glass object during the finishing process. Also called a punty.

Pintil Mark
The mark left on the bottom of the finished piece where it has been cracked off of the pontil rod.

Glass pressed manually or by machine into a mold to form the object, not blown at any stage.

Iron or spring steel shear-like tool used for shaping glass.

A jet of fine sand is blown against the surface of glass to cut a design with the ability to varying depts.

Sandwich Glass
Early pressed glass that originated in Sandwich, Massachusetts and is today prized by collectors. The term also refers to the popular reproductions of this type of ware produced by various glassware manufacturers.

Satin Finish
A soft frosted look acquired by being dipped in a solution of Hydroponic acid.

Bubbles in the glass that are 1/16" diameter or smaller. Usually caused by trapped gases in the molten glass batch.

A glassblower who is first assistant to the gaffer.

Scissors used to cut molten glass.

Shear Marks
Crack-like lines caused by cutting of the glass before pressing .

A gaffer, his assistants, a gatherer, a servitor and a carry-in boy, all working toghter to make an item of glass.

Silk Screen

Enamel is sprayed through an outlined fine screen and firing in the lehr to set the enamel.

A popular decorating process in which a single-color or multi-color design or image is applied to the surface of the glass through a silk mesh, woven wire, or similar screen.

Silver Deposit
A type of decoration in which silver is applied to the glass in the desired design by an electrolytic process, then bonded to the piece by firing.

A layer of milk glass ladled on top of another color already in the pot which when gathered becomes a mixture in all graduations of the two colors.

Smoked Glass

Clear glass darkened for decorative effect by a smoky film applied in open-fired lehrs.

A mechanical device to hold glassware for finishing by hand.

A wash of silver sulfide or silver chloride is applied by brush to areas of an annealed piece of glassware. The ware is then refired at a low tempature.

An inclusion in the body of the glass. Looks like a stone on the interior of the item and can be dark, light or optically transparent. Caused by unmelted batch materials or fefractory materials gathered with the glass from the pot or tank. (can be deadly to the life of the item because of the stress the stone might cause in the surrounding glass.)

A foreign particle on the outside of the glass, usually sticking up form the surface. This is a piece of refractory from the "glory hole" that was picked up when the piece was being "warmed-in". (usually not a problem, execpt cosmetically.)

Stuck Handle

see Cords.

A 4 hour period of time an item is produced and X amount of that item is expected to be made. Example: 900 Cape Cod goblets can be produced in a turn, using 2 moulds.


A novelty glassware item made by the workman for their own amusement or to demonsrate their skills.

Technical Resources