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Glass Bead Glossary of Terms

Glossary of Terms used in Glass Bead Making and Beading

INTRO
Glass beads are usually categorized by the method used to manipulate the glass. Most beads fall into three main categories: wound beads, drawn beads, and molded beads. There are composites, such as millefiori beads, where cross-sections of a drawn glass cane are applied to a wound glass core. A very minor industry in blown glass beads also existed in 19th century Venice and France.

Wound glass beads
Probably the earliest beads of true glass were made by the winding method. Glass at a temperature high enough to make it workable , or "ductile", is laid down or wound around a steel wire or mandrel coated in a clay slip called "bead release." The wound bead while still hot may be further shaped by manipulating with graphite, wood, stainless steel or marble tools and paddles, this process is called marvering, originating from the French word "Marver" which translates to "Marble". It can also be pressed into a mold in its molten state. While still hot, or after re-heating, the surface of the bead may be decorated with fine rods called stringers of colored glass. These are a type of lampwork beads.

Drawn glass beads
The drawing of glass is also very ancient. Evidence of large-scale drawn-glass beadmaking has been found by archeologists in India, at sites like Arekamedu dating to the 2nd century CE. The small drawn beads made by that industry have been called Indo-Pacific beads, because they may have been the single most widely traded item in history--found from the islands of the Pacific to Great Zimbabwe in southern Africa.

There are several methods for making drawn beads, but they all involve pulling a strand out of a gather of glass in such a way as to incorporate a bubble in the center of the strand to serve as the hole in the bead. In Arekamedu this was accomplished by inserting a hollow metal tube into the ball of hot glass and pulling the glass strand out around it, to form a continuous glass tube. In the Venetian bead industry, molten glass was gathered on the end of a tool called a puntile ("puntying up"), a bubble was incorporated into the center of a gather of molten glass, and a second puntile was attached before stretching the gather with its internal bubble into a long cane. The pulling was a skilled process, and canes were reportedly drawn to lengths up to 200 feet long. The drawn tube was then chopped, producing individual drawn beads from its slices. The resulting beads were cooked or rolled in hot sand to round the edges without melting the holes closed; were sieved into sizes; and, usually, strung onto hanks for sale.

The most common type of modern glass bead is the seed bead, a small type of bead typically less than 6mm, traditionally monochrome, and manufactured in very large quantities.They are a modern example of mechanically-drawn glass beads. The micro-bead or "seed bead", are so called due to their tiny, regular size. Modern seed beads are extruded by machine and some, (Miyuki delicas) look like small tubes.

Molded beads 
Pressed glass beadsIncreasing in labor costs are pressed or molded beads. These are made in the Czech republic, in what was once called Bohemia. Thick rods (20cm?) are heated to molten and fed into a rube goldbergian contraption that stamps the glass, including a needle that pierces a hole. The beads again are rolled in hot sand to remove flashing and soften seam lines. By making canes (the glass rods fed into the machine) striped or otherwise patterned, the resulting beads can be more elaborately colored than seed beads. One `feed' of a hot rod might result in 10--20 beads, and a single operator can make thousands in a day.

The Bohemian glass industry was known for its ability to copy more expensive beads, and produced molded glass "lion's teeth", "coral", and "shells", which were popular in the 19th and early 20th century Africa trade.

Lampwork beads
Lampworked dichroic glass bead showing thin film application. Furnace glass beads A variant of the wound glass beadmaking technique, and a labor intensive one, is what is traditionally called lampworking. In the Venetian industry, where very large quantities of beads were produced in the 19th century for the African trade, the core of a decorated bead was produced from molten glass at furnace temperatures, a large-scale industrial process dominated by men. The delicate multicolored decoration was then added by people, mostly women, working at home using used an oil lamp or spirit lamp to re-heat the cores and the fine wisps of colored glass used to decorate them. These workers were paid on a piecework basis for the resulting lampwork beads. Modern lampwork beads are made by using a gas torch to heat a rod of glass and spinning the resulting thread around a metal rod covered in bead release. When the base bead has been formed, other colors of glass can be added to the surface to create many designs. After this initial stage of the beadmaking process, the bead can be further fired in a kiln to make it more durable.

Modern beadmakers use single or duel fuel torches, so `flameworked' is replacing the older term. Unlike a metalworking torch, or burner as some people in the trade prefer to call them, a flameworking torch is usually "surface mix"; that is, the oxygen and fuel (typically propane, though natural gas is also common) is mixed after it comes out of the torch, resulting in a quieter tool and less dirty flame. Also unlike metalworking, the torch is fixed, and the bead and glass move in the flame. American torches are usually mounted at about a 45 degree angle, a result of scientific glassblowing heritage; Japanese torches are recessed, and have flames coming straight up, like a large bunsen burner; Czech production torches tend to be positioned nearly horizontally.


Dichroic glass beads
Increasingly, dichroic glass is being used to produce high-end art beads. Dichroic glass has a thin film of metal fused to the surface of the glass, resulting in a surface that has a metallic sheen that changes between two colors when viewed at different angles. Beads can be pressed, or made with traditional lampworking techniques.

Furnace glass
Italian glass blowing techniques such as latticinio and zanfirico are adapted here to make beads. Furnace glass uses large decorated canes built up out of smaller canes, encased in clear glass and then extruded to form the beads with linear and twisting stripe patterns. No air is blown into the glass. These beads require a large scale glass furnace and annealing kiln for manufacture.


Lead crystal
Lead crystal beads are machine cut and polished. Their high lead content makes them sparkle ore than other glass, but also makes them inherently fragile.


GLOSSARY
Canes
Solid lengths of glass formed by drawing then cut into the desired length particularly for decorative purposes. They can be different colors and patterns, displayed either in on the side or in cross section.

Core formed
Formed by trailing or gathering molten glass around a core supported by a rod. When the object cools, the core is scraped out. This creates a larger and lighter bead since not all of the internal area is filled with glass.

Drawn Beads
A bubble is formed in the molten glass, and then stretched out very, very thin. This resulting tube is then cut into smaller sections forming beads. What was the bubble forms the hole in the center.  The edges can also be worn or polished smooth but tumbling with abrasive materials while heating.

Faience
The oldest “artificial” substance. Probably first made 5,500 years ago. It consists of a core of quartz particles fused together where they touch. A glaze is applied over this. Most faience pieces have lost the glaze because the core and glass expand and contract at different rates as it gets hotter or colder.

Feathered and Raked
This method of decoration is created by applying different colors of glass in lines on the bead and then gently dragging across the surface of the bead.

Folded
Another Middle Eastern style of bead where by the layers of glass are folded over creating the patterned lumpy bead. Sometimes referred to as Torus.

Mosaic/Millefiore
A multi-step process. First the canes are created so that the cross section produces the desired image. These are pulled out until the desired diameter and cut up into slices. These slices are then used for surface decoration of the beads. They can either be applied individually to wound beads, or laid out side by side, cross section up, and fused together, using a mold.

Wound
Wound beads are formed by wrapping molten glass around a mandrel.