A

Annealing is the uniform and controlled cooling of a finished piece of glass. Without proper ' annealing the finished work may eventually crack or break.

 Annealing Temperature Range is the temperature at which molecular stresses are relieved in the cooling process after heating the glass.

 B

Borosilicate Glass (also known as Hard Glass) is a glass composed of boron arid silica. An example would be Pyrex, a brand name of this type of glass.

 C

Cased Beads or Encased Beads are composed of two or more fused layers of glass. The final or outside layer of glass is usually clear or transparent.

Coefficient of Thermal Expansion or COE is the linear measure of how much a material elongates within a given temperature change.

Cold-working is mechanically altering the appearance of glass when it is cold. Grinding, etching, cutting and faceting are examples of cold-working techniques. 

Compatibility refers to types of glass which have the same coefficient of expansion - COE. When glass is heated it expands and when it is cooled it contracts. The ability to contract at the same rate is essential. When glass is incompatible breakage will usually occur.

Controller controls the cooling, heating and maintaining of the temperature of a kiln.

 D

Dichroic Glass appears one color in reflected light and the complementary color in transmitted light. The iridescent appearance is caused by a thick layer of metallic oxides. (di = two; chroic, chrome = color).

Didymium Lenses are used by lampworkers to protect the eye from infrared and ultraviolet radiation from hot glass and to eliminate the yellow sodium flare created when glass is worked in the flame.

 E

Etching is a surface finish that results in a matte or frosted appearance. Hydrofluoric acid, sandblasting and tumbling are all methods used for etching.

 F

Fiber Blanket is a thick insulating blanket made from non-asbestos fibers. Some beads may be prevented from thermal shock by placing them between two layers of fiber blanket so that they can be annealed at a later time.

Filagrana is a rod with a solid color core cased in a clear or transparent color.

Fiber Paper is a high-temperature fiber material made in thin sheets. It is used for mold making and other kiln forming processes.

Fire Polish is to create a glassy finish on glass by the use of heat.

Flame Annealing is a method of slowly cooling a bead in the outer reaches of the flame of the torch.

Flameworking is the manipulation of glass by means of a torch. Frit is crushed glass of varying mesh sizes.

Fuming is the process of melting or burning a metal or metallic salt onto the surface of a piece of glass. The metal, often gold or silver, is heated within a flame until it vaporizes. The vapor is then deposited onto the surface of the glass creating an iridescent glow. Metallic vapors can be toxic. Safety precautions should be taken when fuming.

Furnace-worked Beads are beads that have been made with the use of a pot furnace and glory hole. Traditional glassblowing techniques are often utilized in the production of these beads. Also known as brawn Beads.

Fusing is the process of heat bonding two or more pieces of glass together. This can be done in a glory hole, kiln or torch.

G

Glass is a non-crystalline material with the mechanical rigidity of a solid and the atomic qualities of a liquid. Most glass is composed of silica, sodium oxide and a stabilizer such as calcium oxide.

Glass Enamels are powdered glass applied to and bonded by heat to a heat resistant surface such as glass, fine silver, copper or pure gold.

K

Kiln Casting is the forming of glass within a mold using a kiln as the heat source.

Kiln Wash is a liquid ceramic mixture that is applied to a surface to prevent the hot glass from fusing to that surface. In beadmaking the term bead release is often used.

 L

Lathe is a machine on which a piece of glass is mechanically spun. It is used by glassblowers as a third hand to aid in the forming of glass.

Latticino is a decorative type of twisted glass cane. The Italian word literally translates into "little milk-white strands" and referred to canes made with only clear and opaque white glass. Today the term includes all color combinations of twisted cane.

 Luster is a decorative finish created by applying a metallic oxide to the surface of glass.

 M

Mandrel is a stainless steel rod used in beadmaking. Mandrel Release - see Bead Release.

Mandrel Wound (also known as Wound Bead) refers to beads that have been made on a mandrel. 

Maria - Flattened disk made on the end of glass rod, or Aunty, to provide a wider surface for attaching a glass bundle.

Metallic Foil or Leaf is a paper thin sheet of metal applied to the surface of glass or encased as a decorative element. Fine silver, 22k or 24k gold and palladium are metals most commonly used by beadmakers.

 Millefiori are a specific type of murrine which resemble a flower. Translated from the Italian it literally means a thousand flowers. Millefiori are slices of a mosaic cane that have been built up from concentric layers of glass.

 Mold is a form which is used to shape glass. Typically molds for lampworking are made from metal, wood or graphite. For kiln forming the molds are constructed from heat tolerant fiber paper or a plaster-like investment. 

Murrina (singular) is a slice of cane that has been made by composing different colors of glass to create an image. The design will run the full length of the cane.

Murrine (plural) eau be made using various hot and cold techniques. The end result can depict faces, animals, numbers, letters and other non-linear images.

O

P 

Pontil or Punty is a metal or glass rod used to handle molten glass_

 Pulling Points is to heat, collapse and pull a section of tubing to create a long thin handle.

Premix Torch is a torch that is constructed so that the gasses are mixed inside the torch.

 Press Molding consists of pressing hot glass into a form to achieve a desired shape. Historically beads and glass cabochons, flat-backed pieces of glass set as stones, have been made using one and two part molds.

 Pot Furnace is a heated chamber which holds a crucible or container of molten glass. Glassblowing furnaces are typically powered with gas.

 R

Reducing Flame is a flame which is deficient in oxygen. Using a reducing flame can steal oxygen from metal oxide colorants in the glass making it dull. 

Rod is a straight, round length of glass.

 S

 Soak or Soaking Time is the length of time an object is held at the annealing temperature to remove the internal strain created by heating glass.

 Soda-Lime or Soft Glass is composed of silica, soda and a stabilizer such as calcium oxide. Bullseye and Effetre (Amoretti) are examples of this type of glass.

 Softening Point is the temperature where the glass will slump or deform under its own weight.

 Strain Point is the temperature below which, stress can neither be added nor subtracted from the glass. Below this temperature, the molecules of the glass are "frozen" in place. ..

 Stringers are thin spaghetti-like pieces of glass. They are often used for surface decoration or in creating small details of design.

Surface-Mix Torch is a torch that is constructed so that the gasses are mind at the surface at the face plate of the torch.

T

Thermal Conductivity is a measure of how quickly heat moves through a material.

 Thermal Expansion is the property of a material that when it is heated it is dimensions increase or expand. 

Thermal Gradient is a variation of different temperatures within the glass, 

Thermal Shock is the strain created by abruptly heating and cooling a piece of glass. Glass can be thermal shocked when it is heated or cooled too fast and breakage will occur.

Torch is a heat source used far lampworking. A mixture of compressed oxygen and fuel gas (such as propane natural or MAPP) is burned.

Tumbling is the technique of abrading the surface of glass using an electronic tumbling, machine and various metal or plastic media and chemical compounds.

Twistie is a rod or stringer made by twisting two or more colors of glass together.

V

Viscosity is the measure of the amount of force needed to make a material flow.

W

Working Range is the temperature needed to form an object form glass.

Wound Bead - see Mandrel Wound.