Terms Related to Art Glass and to Glass Working/Crafting

Including Terms for Fused Glass, Stained Glass, Dichroic Glass, and Blown Glass

Acid Etching – process of cutting a design into glass using acid as the cutting agent. The pattern to be etched is transferred from an etching plate to the surface of the glass with an acid resist made of beeswax. The vessel is then exposed to hydrofluoric acid or acid fumes, which etch the unprotected surface areas, thus leaving a frosted design when the protective layer is removed. Some companies used a metal etching plate rather than a resist to protect the areas that were to remain unaffected.

Acid Finish – matte finish produced by exposing surface of a glass piece to acid fumes during finishing or, in some cases, with a mechanical grinding wheel (also see Satin).

Amberina – glass piece shaded from red at the top to amber at the base, produced by cooling and reheating the top portion of the piece.

Annealing – moving glass on a conveyor belt (or, on a smaller scale, in a kiln) through a hot chamber and then a cooling tunnel to gradually cool hot glass. This process removes stress from the glass. This is done between the cooling of the glass from 1000° degrees Fahrenheit down to 600°degrees Fahrenheit.

Annealing Point – The temperature, at the upper end of the annealing range. Reaching this normally prevents stress fractures and breaking.

Annealing Zone – The temperature range beginning at the softening stage and ending at the strain point.

Applied – attaching a handle or other piece of molten glass to a glass vessel by hand, most commonly in hand or mold blown glass techniques, but also in early pressed glass pieces.

Appliquéd Glass – decorative glass featuring three-dimensional glass trim, applied to a piece by hand in a molten state after the piece itself has cooled, often in fruit or flowering vine patterns.

Art Glass – Colored glass used in glass fusing and stained glass. It may have certain properties required for fusing. Alternate meaning – Any glass item, such as a vase, considered “pretty” and coveted by collectors.

Aventurine – copper or other metal oxides suspended between a clear outer layer and colored inner casing of glass, forming crystals that reflect light, giving a glass object a shimmering appearance.

AOP or All Over Pattern – differentiation of Depression glass pieces within the same pattern but which have variations. An example would be a dish or tumbler with an AOP instead of just a decorative band on the rim.

Bails–Arched hooplike pieces that are attached to glass pieces, allowing you to hang the glass piece on a chain or link it to another object.

BENT (or Slumped) GLASS – Glass which has been heated in a kiln from room temperature to a temperature high enough to cause it to soften and slump (sag) into or over a mold. The finished item takes the shape of the mold.

Batch – a batch of materials used to form glass pieces, with silica, potash and soda ash being the primary ingredients used in glassmaking.

Bevel – Cold glass (usually clear, thick plate) with edges that have been ground and polished to an angle other than 90 degrees. Transmitted light is refracted and a prism-like effect results. Bevels are available in a variety of sizes, shapes and geometric configurations (called “clusters”) for incorporation into leaded

Billet – A glass ingot, similar to a dalle, used in glass casting

Blank – The bottom layer of glass on which other pieces of glass are placed before fusing.

Break – When glass separates and becomes two or more pieces. Unlike “smashing glass” this is not a bad thing in glass work (it is a desired result in glass cutting)

Breaking Pliers – Used like your hands to break off glass at the score line.

Brittle Zone – Also referred to as the cold zone. This is from room temperature to about 900 degrees Fahrenheit.

Burn Out – Pre-firing material in a vented kiln to remove any undesired contaminants.

Butter Pat or Chip – small round or square dish used to hold butter on a Victorian table, only a few w were produced in glass, notable cut glass.

Came – Channeled strips of lead, copper, zinc or other metal used to bind glass pieces within a design. (See leaded glass)

C.O.E. — (See coefficient of expansion)

Cameo Glass – ancient Roman technique, revived in England in the 19th century, using multi-layers of glass, with an opaque white outer surface carved by hand or acid etching to create designs by exposing the colored inner layer.

Cane – glass rod used in glassmaking to produce effects like stripes or twisted filigree.

Cased Glass – two layers of contrasting glass fused together, creating a single piece, with the inner layer sometimes blown into the outer layer, or a piece of one color dipped into molten glass another color while still hot. Cameo is one form of cased glass.

Cast Glass – A glass art medium in which glass is melted in, or melted and then poured into, a pre-shaped mold to create a finished project.

Cast Figure Mold – process perfected by Reuben Haley and used to create his unique Martele hand wrought glassware; a glass mold is cast from a sculpted model to transfer fine details without additional milling.

Cast Glass – A glass art medium in which glass is melted in, or melted and then poured into, a pre-shaped mold to create a finished project.

Casting – Pouring hot molten glass into a mold to achieve a desired shape.

Cathedral Glass – Describes transparent glass that is monochromatic — i.e., single color sheet glass, with smooth or textured surfaces.

Catspaw – (Single Roll forming method.) 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.

Ceramic Fiber Insulation – A refractory material that is made from spun fibers.

Chip Mold – glass mold technique in which a pattern is cut or chipped with hammer and chisel into an iron mold’s surface.

Chop Plate – a large, flat serving plate, also sometimes called a salver.

Circle Cutter – Scores ovals and circles on flat glass. It is easy to operate and has a suction cup that secures the cutter to the glass.

Cobalt – a very dark blue color produced by adding cobalt to a batch.

Coefficient Of Expansion – The ratio of the change in length or volume of a glass to its original length or volume per unit change in temperature. Used to help determine compatibility of different glasses for the fusing process.

Cold Combing – The process of achieving the look of combing without working inside a hot kiln.

Cold Working – Working with or changing glass in its natural state. This could involve sanding, grinding, drilling, or sandblasting.

Combing – Process in which a rake-like tool is drawn across molten glass to create artistic patterns.

Compatable or Compatability – Glasses are said to be compatible if, after being fused together by blowing or kiln forming and properly annealed, they remain relatively free from internal stress.

Comport or Compote – a small, open-bowl candy dish with a stem and base.

Confetti – Paper-thin elements of glass that can be incorporated into a fused or blown glass design. Also called “shards.”

Console Set – a matched set usually containing a center bowl and a pair of candlesticks, popular in the 1920s and 30s, either mold blown or pressed.

Controller – The switch on a kiln that allows you to turn it on or off, with different positions in between for heating rates.

Copper Foil – Thin, narrow strips of adhesive-backed copper tape is used to wrap the edges of glass pieces that have been cut to fit a pattern. Once wrapped, solder is applied, bonding the glass pieces together. Assembling a stained glass project in this manner is called the “copper foil technique.” Louis Tiffany is credited with its development.

Cracker Jar or Biscuit Jar – Victorian era equivalent of a modern day cookie jar, made with glass or china, usually barrel shaped, with a silver plate rim, cover and bail handle.

Crackle, Crackled or Craquelle – also called Iced Glass, a mold or hand blown glass object, while hot, is plunged into cold water before blowing to produce a finely crackled outer surface and smooth interior.

Cranberry – transparent, reddish-pink color of glass, produced by adding gold oxide to a batch, originated in the 1820s and popular through the 1880s.

Crimping – decorative ruffle or ribbon design around the rim of a vase or bowl, achieved by manipulating the shape with a tool while the piece is still hot.

Custard Glass – an opaque milk glass variation in colors varying from rich, creamy yellow to bone white with an opalescent finish; Uranium salts were added to batches used to produce antique custard glass, so that it will trigger a Geiger counter needle to move and also glows under a black light.

Cutter – The technical term for this would be glass cutter. This is a tool consisting of a handle and a beveled cutting wheel.

Cutter Oil – A high-viscosity fluid used with a glass cutter. The oil keeps the wheel clean of dust and glass chips, which increases the life of the cutter.

Dalles – Thick (usually 1″) slabs of cathedral glass.

Dalle de Verre – An art glass medium in which dalles are broken into pieces with a carbon hammer and set in an epoxy base to adhere them to a decorative design. Dependent on large scale for best appearance, they are primarily used in architectural applications such as church walls.

Devitrification – A crystalline substance that appears as a foam or dull finish on the surface of some glasses when heated above 1000° F. This is caused by the glass going through a change in the texture from glassy to crystalline.

Devitrification Spray-This spray is applied to the surface of glass before firing to avoid devitrification and helps to give the piece a shiny exterior.

Dichroic – Commonly used term to describe glasses that have been coated with one or more ultra-thin crystalline layers of transparent metal oxides designed to enhance reflections at specific wavelengths of light. The process occurs in a vacuum chamber at elevated temperatures. The resulting effects are striking and show brilliant color reflections at varying angles of incidence.

Domino Tray – named for the Domino Sugar Company, produced by Depression glassware makers in the later 1920s and 30s; a round tray with center ring designed to hold a creamer sugar cubes.

Drapery Glass – Glass sheets with multiple dramatic folds, likened to those in hanging drapes.

Dust Mask – Fits over your nose and mouth to protect you from breathing in harmful dust, or glass particles.

Elements – Wires inside the kiln that produce heat.

Enameled Decoration – decorative glass technique commonly used in Victorian art glass, hand painting glass decorative technique using white or colored enamel paints applied on a finished glass piece and re fired to bake the enamel finish.

Enamels - This technical term refers to a paint made from finely ground glass and pigments that can be used to add color. Then they are fired on to the glass.

Epergne – 19th century glass vessel with a tall, trumpeted vase fitted into a wide, shallow bowl base, foot or pedestal.

Etched Mold – glass mold technique with pattern etched into the surface, achieving very fine detail in pressed glass.

Etching – patterns or designs cut into glass either by acid etching or needle etching techniques.

Expansion Coefficient – A numerical designator assigned to a glass to describe its Coefficient of Expansion.

Fiber Paper – Thicker than thin shelf paper, used to protect the kiln shelf and for making channels in glass. Can be used many times.

Fine Silver Wire – This wire will shine up to bright silver after it is fused.

Firing Log – Log of various firing schedules. Assists in understanding what has happened in past procedures.

Fired On – applying color to the surface of a glass piece, then baking it to permanently fuse the color to the piece.

Fire Polishing – technique in which glass is reheated to smooth mold seams without distorting the pattern on a mold blown or pressed glass piece.

Firing Schedule – Written details of the times and rates of heating and cooling during a particular cycle.

Fit – Compatible glass is said to “fit” each other

Flashed – (Flash Glass) Glass of one color with a very thin layer of another color on one side. Flashed glass is often used for etched or sandblasted glass art. When sections of the thin color layer are removed, the base color shows through.

Flashed On – highlighting crystal glass with colored stain, commonly amber or red, by reheating the piece to fuse or flash the color to the surface of the piece, tends to rub off more easily with use than color which is fired on.

Flash Venting – Opening the kiln door or lid during the firing process to stop the process.

Float Glass – Commonly known as window glass. It has been created by flowing molten glass on a bed of hot tin. This causes it to have a shiny polished surface on both sides of the glass.

Fluid Zone – Also referred to as molten zone. Glass becomes fluid like and can flow. This occurs above 1350 degrees Fahrenheit. Fusing of the glass occurs around 1500 – 1600 degrees Fahrenheit.

Flux – Chemical agent (liquid or paste) used to facilitate the flow of solder and prevent formation of oxides during soldering (Stained glass work term).

Freeze and Fuse – The process of mixing powder glass and water in a flexible mold, freeze and then fired in a kiln. The technical term for this procedure is “pate-de-verre”

Frit – Ground glass, ranging in particle size from gravel-like to a fine powder. Frit is sometimes used as a raw material in glass manufacture, and sometimes as a coloring agent or for decorative effect in hot glass crafts like blowing and fusing.

Frit Casting – Filling a mold with frit and heating it until the frit fused into a solid mass.

Fritting/Sintering The process of creating frit.

Full Fusing – Heating two or more pieces of glass until the melt and flow together.

Furniture – Ceramic posts used in a kiln for shelves or glass.

Fused Glass – Glass forms produced by placing different pieces of glass in contact with each other in an arranged design, then firing them in a kiln at a temperature high enough to fuse them into one piece of glass.

Fusing Gloves – Gloves used to pick up hot glass and for opening up your kiln while it is in the fusing process.

Fusing Glue/GlasTac Glue/Elmer’s Glue – These technical terms are liquids used to hold glass pieces in place while transferring them from your work place to the kiln shelf.

Frog – fitted into a bowl or the neck of a vase, a Frog is a heavy glass disc with holes designed to hold a flower arrangement; Figural Frogs have a figurine in the center.

Gather – using a punty rod or blowpipe, a glassblower “gathers” molten glass on the end of the rod or pipe.

Glass Casting – When you heat glass until it melts, and then it is poured into a mold.

Glass Cleaner – Any commercial ammonia-free glass cleaning product, soap and water or vinegar. Always use a lint-free towel when drying glass.

Glass Compatibility – The technical term for making sure that every piece of your glass expands and contracts at the same temperature.

Glass Cutter – Used to score (scratch) the glass. See cutter above.

Glass Paints - Pigments, powdered or liquid glass paints applied to a glass surface

Glass Saw- Used to cut any glass shape out of any type of glass, quickly and with minimum glass waste.

.Glob – (See nugget)

Glue-Chip – A texture created on the surface of cold glass by applying hot animal glue and allowing it to dry under controlled temperature and humidity conditions. As the glue dries and contracts, it chips the glass surface in a natural and attractive pattern, likened to frost on a window pane.

Goggles – Used to protect your eyes while working with glass. Not used during firing techniques, will not protect against glare, ultraviolet and infrared radiation.

Gold Pen – Pre-filled pens for adding fine trim, detailed designs, enhancing and personalizing your glass.

Gold Pink – Common name for colored glasses in the pink/cranberry/fuchsia range that require gold oxide as a coloring agent.

Graverre – The graphite or charcoal drawing is fused between layers of the glass sheets. The technique is ideal for capturing the spontaneity of drawing.

Grill Plate – popular in diners and grills in the 1920s and 30s; a plate with raised ridges dividing it into three sections to separate food.

Grinder – Electrical tool that is used for the precision shaping of glass.

Grinding – Using an abrasive wheel on a grinder to smooth or shape the edges of glass.

Groze – The process of filing or chipping away a small amount of glass.

Grozing Pliers – Used for grozing glass. They have small serrated teeth

Haik Brush – Used to apply shelf primer to kiln shelves and molds

.Handkerchief Vase – style of 20th century Venetian glass vase with the sides pulled up and pleated into interesting shapes, giving it the appearance of a handkerchief.

Hard Glass – A glass of high viscosity at elevated temperatures. Has a high softening point and is difficult to melt.

Hi-temp Wire – The technical term for this would be High temperature wire. Rated at 2000′ Fahrenheit. High-temperature wire is sometimes used for making connections in fused glass jewelry. This wire will hold up to fusing temperatures, but will fire scale a bit and turn almost gray.

High Temperature Gloves – Safety gloves worn when hands are exposed to dangerous temperatures.

Hot Glass – Working with or manipulating glass while it is in a molten condition.

Hot Metal Man – also called a Batch Man or Color Man, supervises the mixing of glass batches and formulates the recipes, which are often the hallmark of a glass company.

Incalmo – Italian decorative glassblowing technique.

Inclusions – Any object fused between two layers of glass.

Iridescence – a type of multi-hued or rainbow colored finish which is achieved by spraying metal salts onto hot glass and then re-firing the piece.

Ice Lip – fold that is molded around the lip of a pitcher, preventing ice from pouring into a glass along with the water, iced tea or other liquid.

Jack-in-the-Pulpit Vase – a style of vase made to look like the flower by manipulating the rim to curl the back edge upward and the front edge downward.

Jewel- A piece of glass that has been cut and faceted or press-molded into a geometric shape like a jewel. Often incorporated into leaded glass artwork.

Jewelry Findings – Everything you need for jewelry making.

Jewelry Glue – For glass projects most people use E6000 or two part epoxy glue.

Kiln – Thermally insulated chambers, usually made out of fire bricks.

Kiln Forming – Using a kiln to heat and form glass.

Kiln Posts – These are put under your kiln shelf to raise it up. They are good for high temperatures have fluted sides.and a hole in the center.

Kiln Shelf – These can come in different sizes and shapes and should be purchased to fit your kiln. They come in round, half round, rectangular, square, multi sided, hexagonal, octagonal, 10 sided and 12 sided. You place your items on this when you are going to fire them in the kiln.

Kiln Sitter – A devise that is set to automatically regulate the temperature inside a kiln.

Kiln Wash – This is a refractory powder that can be mixed with water and painted on kilns, kiln shelves and molds to prevent glass and accidental glaze drips from sticking.

Knop – refers to a knob or finial on the lid of a glass vessel or the bulbous part of the stem on a wineglass or goblet.

Laminate – Using heat to bond glass to the point of just sticking together.

Lampwork or Lampworking – using a torch or small flame, called a lamp, to form delicate glass objects from canes.

Latticino – Italian term that refers to a technique developed by the Romans and used in Murano glassmaking in which spiraled threads of white or colored glass are embedded into a piece of clear crystal.

Lattimo – Italian term, meaning latte milk, refers to opaque white or milk glass.

LEADED GLASS – (1) Sheet glass pieces joined with metal strips, usually made of lead, called “came.” Solder is applied to the joints of the came to bond the work together. (2) Glass containing lead as a raw material (as in “leaded crystal”).

Lehr - a specialized, temperature-controlled kiln for annealing glass.

Liuli – ancient Chinese glass art.

Mandrel - metal rod used to make the hole in a glass bead

Milk Glass – opaque white glass; early milk glass pieces are opalescent when held up to a light source.

Marver – a tool used in glassblowing.

Millefiori – meaning “thousand flowers” in Italian and also called Tessera, or tile work; a technique in which glass rods are cut into discs and placed into a mold to form a decorative pattern, then re-fired to fuse the pieces together.

Mold or Mould – a pattern is made using wood or plaster and used to produce a rough iron cast in a metal foundry, into which molten glass can then be poured to produce glass molded pieces, milled and shaped, and then the design etched or cut into the surface.

Mold Blown – molten glass is blown into a mold to produce a glass object with the pattern of the mold.

Mold Pressed or Press Molded – molten glass is poured into a mold, and then a plunger presses glass into the mold evenly to produce a glass object.

Molds – Used for glass slumping, and fusing. They can be used to make jewelry, plates, bowls, etc. They come in a variety of shapes and sizes.

MOSAIC – A picture or decorative design made by setting small colored pieces of glass or ceramic material into a surface using cement or grout as a bonding agent.

MOTTLED GLASS — (See Ring Mottle.)

Murano Glass – refers to glass made in Murano, Italy or elsewhere using techniques like hand blowing and many others developed or refined over the centuries by glassmakers in Murano.

MURRINI – A thin slice of complex glass cane that can be used as a component in another glass object.

Nappy – refers to a bowl.

Needle Etching – technique developed in the 20th century; a hand held or mechanical needle is used to draw fine and sometimes ornate, repetitive designs on a glass piece.

Needle Points – Sharp pieces on the edge of glass that are formed when the contracting glass sticks to parts of the kiln wash.

NOODLE – A fetuccini-like glass shape used as a decorative element in the hot glass arts.

Novelty – a small scale glass version of some larger object, like an animal, sword, ship, etc. and popular in the late 19th century as boxes, toothpick holders and similar items.

NUGGET – A small, irregularly shaped “glob” of glass, flat on the bottom, rounded across the top. Nuggets are made by literally dropping a small amount of molten glass onto a flat surface. Frequently called “globs,” they are often incorporated into leaded glass artwork.

Opal – 19th century term; refers to what we now call milk glass.

Opalescent – meaning semi-translucent, refers to white colored glass that shows some orange or “fire” translucence when held up to a direct light source, usually around the edges of the piece, flowing into a different color of glass.

Ormolu – refers to decorative metal added to an object made of glass.

Overshot – achieved by rolling a gather over a steel plate on which small glass particles are placed, reheating the object to melt the sharp edges of these fragments, and then blowing the object to its final size and form, giving the object a rough texture and nicely speckled color.

PAINTED GLASS – Glass on which special paints (containing frit) have been applied in illustration or decorative pattern and then heated in a kiln to a temperature high enough to fuse the pigments permanently to the glass surface. The modern version of the original medieval “stained glass.”

PATE de VERRE – An art glass medium in which powdered glass frits are spread in a decorative design, then fired in a kiln.

Pattern Bar – A bundle of glass that has been fused together to form a solid shape.

Pattern Slices – Thin slices cut off a pattern bar.

Peep Hole – A small opening in the kiln used for observation of glass during firing process.

Piedouche – French term referring to a paperweight which is raised up on a pedestal foot.

Pliable Zone – Also referred to as the workable zone. Glass will begin to slump or move from about 1250 degrees Fahrenheit to 1350 degrees Fahrenheit. This is the zone where glass slumping occurs.

Pontil 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.

Powders – Glass that has been ground into a fine powder. It can be used to decorate glass before fusing, mixed with liquid stringer and used as paint, or mixed with water and used in the Freeze and Fuse method.

Prefire Adhesive – Glue that can be used to hold glass in place before firing.

Prunt – a small blob of glass fused to a piece of glass, often impressed with a pattern or stamp.

Punty Rod or Pontil Rod – refers to the metal rod a glassmaker attaches to hot glass so that it can be handled while hot as the piece is shaped and finished.

Pyrometer – A high-temperature thermometer that measures the heat inside a kiln.

Ramp Time – The time required for the kiln temperature to increase or decrease. The amount of time stated in each step of a firing schedule for your kiln to go from its current temperature to the next indicated set point, in consistent degrees per minute.

Ramps – This term refers to the rapid heating cycles.

Reaching Tongs – Used to reach far into your kiln to put in or remove items. They are also great for picking up and working with hot items in the kiln. They have serrated tips that help in grabbing your item. These are made from stainless steel.

REFRACTORY – High-temperature brick used to construct ovens for melting glass.

Reticello – Italian decorative glassblowing technique.

Rigidizer – A chemical added to certain ceramic fibers to bind them into a solid state.

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.

Rigaree – a form of appliquéd glass decoration in a crimped, a ribbon-like highlight on some Victorian art glass pieces.

RIPPLE – A surface texture, often dramatic, consisting of linear or irregular ripples. Created naturally in some sheet-forming processes, imitated with an embossing roll in others.

RODS – Used to describe cylindrical, pencil-thick sticks of glass used primarily in flameworking and glass bead making. They are available in a wide color range and many expansion coefficients.

RONDEL – 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 Bowl – popular 19th century bowl with edges curved inward and a small center opening, typically tri-footed and used to display small rosebuds or potpourri of rose petals.

Ruby Glass – refers to transparent, dark red colored glass.

Run – When the glass begins to break at one edge and runs to the other edge.

Running Pliers – Used to control the breaking of the glass. They are placed on the edge of the glass and when squeezed the pressure causes the glass to break.

Safety Glasses – Safety glasses provide protection against glare, ultraviolet and infrared radiation. If they fit close to your face, they can be used during glass cutting.

Sagging Process – Heating glass until it sags and conforms to the shape of the form on which it rests.

Salver – also called a chop plate; serving plate, typically 11 to 13 inches in diameter, without handles.

Satin – refers to acid finish; use of hydrofluoric acid to produce a velvety, smooth glass surface.

Scalloping – refers to decorative ruffles or wavy shape given to the rim of bowls, vases and other glass items during the molding process versus crimping, which is hand done after molding.

Score Line – A light scratch on the surface of glass when the cutter is pressed against the glass and then drawn or pushed across the surface.

Seeds – Air bubbles that are trapped in glass during the manufacturing process.

SEEDY GLASS – Glass in which air bubbles are entrapped. Air or gas is injected into the molten glass prior to forming the sheet.

Serrated – refers to a notched or sawtooth edge on the rim of a glass piece, usually found on cut glass pieces.

Set Point – A goal temperature of the kiln in any given step of a firing schedule.

Shards – Pieces of glass broken off from larger glass sheets, or objects.

Shelf Primer – Used to keep glass from sticking to kiln shelf. Sometimes called kiln wash.

Shop – refers to a glassmaking crew that works together, hand making glass items and glass art pieces.

Shotgun Annealing- The process of taking glass through different annealing points.

Side-firing Kiln – The elements have been placed around the sides of the inside of the kiln.

Silver Deposit or Silver Overlay – complex glassmaking technique that uses electrolysis to deposit a metallic silver design painted on a glass piece with a wash of borax, oxide of lead, sand, nitrate of potash, white arsenic and phosphate of lime mixed in turpentine, the piece is then fired, submerged in an electroplating bath to deposit the silver, and finally buffed and polished.

Sickness – refers to cloudy stains in glass vessels such as vases, decanters and bottles, caused by chemical reactions inside the vessel when liquid is left in it for a long period; can sometimes be cleaned or may required re-polishing the piece.

SLUMPED GLASS — (See Bent Glass).

Soak – To hold the kiln at a steady temperature for a specific length of time.

Soak Time – The length of time to hold the temperature of the kiln at a certain set point or temperature before continuing to the next step.

Soft Shoe Brush – Used to clean your work surface after cutting glass.

Softening Point – The point at which glass when heated starts to soften and bend.

SOLDER – A fusible alloy, usually tin and lead, used to join metallic parts, or the act of applying it. Used to bond metals in both the leaded and copper foil techniques of stained glass work.

Spall – A shallow rounded flake on a glass object, generally near the rim of a piece.

Spatter – similar to Overshot, a technique producing spotted or multi-colored glass with white inner casing and clear outer casing by rolling a gather in tiny particles of glass; Spatter is cased, resulting in a smooth surface, whereas Overshot glass is left rough and uneven.

Stacking – The layering of sheets of glass to create patterns or images.

STAINED GLASS – Commonly used to describe any colored flat glass or any object made of such glass joined by metal strips. The term originally applied to colored or clear flat glass cut to fit an artist’s design, on which details were painted in pigment with a brush. The glass pieces were then heated in a kiln or oven to bond the pigment to the glass surface. This firing makes the painted detail as durable and permanent as the glass itself. Most religious windows from medieval times until this century were executed in this manner, and so the term came to be used first for any architectural application, and then for any design in colored flat glass. It is now universally accepted as a convenient general term to define the art, the craft, and the industry.

Stemware – refers to a drinking vessel with a bowl set on a slender pedestal or base with a stem.

Strain Point – This is the lowest annealing temperature. If there is any stress in the glass at this point, it is permanent.

Stress – The tension in glass that could cause it to break.

STREAKY GLASS – Two or more cathedral glasses mixed together to create a multi-colored glass sheet. Some use this term also to describe Mixed Opalescent glass.

STRINGER – A spaghetti-like glass shape used as a decorative element in the hot glass arts.

Tack Fusing – Fusing glass until it just sticks together. Each piece still retains its individual character.

Teardrop – refers to an inclusion caused by an air bubble, purposely created in a glass item for decorative effect to highlight a feature such as the stem of a goblet or the stopper of a decanter.

TERRAZZO – A combination of marble, granite, onyx, or glass chips in a binder of portland cement or other resinous material. After curing, the surface is ground to expose the decorative chips.

TESTED COMPATIBLE – Descriptive of glasses which have been tested and marked prior to sale to verify compatibility with each other when combined in a hot glass process like blowing, fusing, or casting.

Texture Fire – Fusing glass to the point where it is bonded and the texture remains on the individual pieces.

Textured Glass – A rolled texture is imprinted on the glass as the sheet is being formed. A natural texture is created without mechanical inducing. A cold glass texture includes etching or any surface treatment performed on room temperature glass.

Thermal Shock – Breakage that occurs in glass because of rapid heating or cooling.

Thermocouple – The probe of a pyrometer. It is inserted into the kiln to measure the temperature.

Timer – A device with an alarm to remind you to check your glass in the kiln.

Top Firing Kiln – The elements are placed in the lid of the kiln.

Transitional Zone – Glass begins to change from about 900 degrees Fahrenheit to 1250 degrees Fahrenheit. The strain point is at the lower end of this temperature, while the upper end is where the softening point and the annealing point are near the same temperature.

Tumble Up – long necked glass bottle that was often placed on a nightstand, having a small, upside-down tumbler seated on top so that the tumbler was used both as a stopper and drinking vessel.

Turn – refers to a shift worked by a shop and measuring output by how many pieces were produced rather than the number of hours worked.

Twistie, a cane formed out of different colored glass twisted together.

Venting - The process of opening the kiln lid or door during the fusing process.

Viscosity – A liquid’s internal resistance to flowing

Vitrograph - The act of maneuvering molten glass as it flow from the bottom of a raised and supported kiln.

Vesica – refers to a decorative, pointed oval design cut into a glass piece.

Water Set – a set of\ tableware containing a large pitcher and six or more goblets or tumblers, and sometimes also including a matched tray.

Wedge Venting – Using a wedge of 1/2 inch to 1 inch to vent the kiln during firing.

Wet Felt – Soaking a ceramic-fiber with rigidizer and using it for mold making.

Whimsey – also known as Lunchpail Pieces, whimsies are pieces created by glassmakers as special gifts for loved ones or close friends, with special or unique features, rarely sold on the open market and fetching extremely high prices from collectors attracted to the work of a given shop.

Wire - The act of using wire to enhance a piece of artwork.

Wire Wrapping – The act of using wire to enhance a piece of artwork.

Wire Wrapping Tools – The use of tools to bind and twist wires together. Some of the tools used include pliers and wire cutters.

Zanfirico – Italian decorative glassblowing technique.

Note: Please feel free to contact me to add a term of your own if you feel it should be added to the list above. Jerry (webmaster, Crafting Glass) 

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