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From time immemorial people have made beads from a broad variety of materials, beginning with found objects that had interesting shapes, colors, or patterns, and that were easily altered with the usable technology of the time.
Once technology facilitated the cutting, grinding, and drilling of materials, beads were made from more durable substances. By the 3rd millennium BCE, there were crafts-specialists whose daily jobs were to make beads and ornaments, and significant processes were devised to create these beautiful objects.
STONE BEADS
In general, softer stones were exploited before harder stones. However this does not necessarily mean that all soft-stone beads are older than hard-stone beads. Beads are closely allied to the tools of their period, since they result from using those actual tools, and they share characteristics in common with the tools of production. The typical stone bead is roughed-out (crudely or basically shaped), refined via grinding or abrasion, and finished by polishing. Stone beads also require drilling to provide a perforation. Each of these steps is regarded as typical of lapidary work.
We know that well before 3000 BCE beadmakers had already discovered that heat-treating certain stones made them harder and stronger, and changed their colors. Consequently, it's safest to assume most stones have been enhanced. By 2,500 BCE artisans were painting patterns onto agate beads, heating the material to make designs permanent, resulting in what are called "etched" or "decorated" beads.
Although minerals were selected for various qualities, they were also used because of what could be done to alter and improve their appearance. In examining ancient beads, we become aware that not all beads have survived well in their interment. Environmental factors often compromise the appearance of beads, making them dull, or covered with a superficial (or deep) decay or discoloration.
CERAMIC BEADS
Although the use of clay was significant for the production of vessels such as plates, bowls, and jars, its exploitation for beadmaking was not as extensive in ancient times as many might assume. There are exceptions, of course. China excelled in making ceramic beads from early times and continues to make them. In the Middle East, ceramic beads were not common.
The material we have come to call "faience" is classified by some as a sort of "ceramic." However, it was mankind's first artificial material, and is more aptly thought of as the ancestor of glass.
FAIENCE
Faience and glass are composed from silica (deprived from pulverized quartz and/or sand) combined with elements that help fusion and provide color. Faience has a pale interior, and is normally glazed on the exterior—and this glaze itself is basically glass, that is colored via mineral oxides.
Closely related to faience is what antiquity named "kyanos" that we usually call "Egyptian Blue." This material was colored various blue tones through its mass, and was not only a material for carving and hot-worked ornaments, but also for pigmenting paint, and other uses.
Faience and similar pastes (“glassy faience,” “frit,” etc.) were produced at Egypt and the Near East, spanning more than 5,000 years. They were made into beads, pendants, and other ornaments and artifacts via modeling and molding, may have been self-glazing or separately glazed, may be monochrome or polychrome, and present some of the most delicate and cunning art that survives from antiquity.
GLASS BEADS
Glass most likely developed in antiquity out of the combination of two technologies:
of using a draft furnace (as for metal smelting) with the components typical of faience manufacture. This occurred in Akkadia in the mid-second millennium BCE.
The exploitation of glass demanded entirely new approaches in manufacture, since glass had so many unexpected properties, as well as particular requisites. Whereas faience was worked in a doughy state at ambient temperature (similar to clay and other soft viscous products), glass was only malleable while it was hot, and could only be manipulated with tools. The cooling of glass that allowed it to stiffen and harden also required “annealing”—controlled cooling, to prevent stress fractures and breakage.
So the technology of glassmaking was complicated, and for a long period, was in the hands of a limited number of artisans. Although we tend to think of glass as transparent or translucent, and also colorless, early glass was generally opaque or feebly translucent, and was most often colored to resemble desirable materials. In particular, it was made violet-blue to resemble lapis lazuli, and teal-blue to copy turquoise.
It is helpful to understand that the remarkable versatility of glass makes the classification and naming of artifacts complicated. Glass beads are usually grouped together or segregated by the primary techniques exploited in their manufacture. We respect these traditional divisions in the following types of glass-beadmaking and naming.
Wound Beads
One of the simplest and earliest ways of making a glass bead is to withdraw a small quantity of the molten material, from a crucible, and to apply it to a metal wire or rod, a "mandrel." — Turning this “mandrel” to wind-up the thread of glass, much like fiber is wound onto a spool, produces a rounded lump. The bead is removed from the mandrel, and is thus provided with a perforation.
In antiquity, the majority of wound beads were made at a furnace, from molten material in a crucible. Thus, these are called “furnace-wound” beads.
In later times, a set-up was made first (a preformed element of monochromatic or polychrome glass), and the set-up was reheated and used in beadmaking.
At some point in time, a small heating apparatus (today it’s the gas torch) was devised for limited-production work. Europeans referred to this appliance as a “lamp,” and gave us the term “lampworked” for the beads they made.
Wound beads, in contrast to furnace-wound beads are sometimes called “lamp-wound” beads. These do not exist from antiquity—and when we see lampwork beads being so-represented, we know this is an error.
Wound beads are recognized by the fact that the fabric of the glass flows around the axis (mandrel or perforation) of the bead, as do bubbles and contaminants that are in the glass. In antiquity, the mandrel was generally pig-iron, rather thick in diameter, and often tapered. This facilitated removal of the bead from its mandrel.
In modern times, the mandrel may be coated with a clay-slip compound that helps prevent sticking; or often a thin “wire” is used, and this is dissolved with acid to clear the perforation. These characteristics help to establish the identity of a glass bead.
Hot-pierced Glass Beads
Any semi-molten lump or quantity of glass can be manually perforated by being poked with a metal spit, and on this handle can then be shaped and altered. In antiquity many less-skilled workers made such beads.
In Hellenistic times, when mosaic-glass techniques were devised, a mosaic-glass set-up could be similarly used. In this instance, typically, a piece of multicolored cane or a bar would be heated and pierced, and then shaped as before. The manufacture of hot-pierced beads persisted well into the Islamic Period.
Molded Glass Beads
The molding of glass beads occurs today, but appears to be very different from the typical processes of antiquity. In ancient times, a mold was prepared having the inverse shape of whatever was desired to be imparted to the beads being manufactured. Usually, the mold had one surface (the bottom of the mold, making the front of the piece) that had convolutions to impart a shape or design.
The glass could be charged into the mold in either of two ways: 1) small bits or even powdered glass filled the mold; or 2) a semi-molten glob of glass was forced into the mold and withdrawn. In the former instance, the mold would be heated until the glass fused. The withdrawl of the molded glass from the mold was probably facilitated by the use of a releasing compound. The details of this work are largely unknown and have required speculation.
The use of two-part molds, to make items shaped in-the-round may have been exploited in later times (say, the Roman Period),
but this moves into the category of being “press-molded” beads—where the bead already exists prior to being altered.
This is not actually “molding,” but rather is “pressing.” Molded and pressed beads often display a seam that results from these processes.
The seam may be longitudinal, along an edge, or around the axis—depending on the mold used and the shape of the resulting bead.
Lapidary-Made Glass Beads
Glass can be altered in a “cold” (non-molten) state, by exploiting the same processes used for stone-beadmaking. A shape is roughed-out, ground and abraded, polished, and drilled. It is easy to speculate that such work was done in areas where stone beadmaking was practiced, and where hot-glass skills were not known. Lapidary work typically results in a bead that looks very much like a stone bead. Lapidary skills were also applied to many glass products, for refining shapes, getting rid of unnecessary parts or flaws, and to polish surfaces. However, the term is used for objects that fundamentally result from these processes, and not those that are merely finished with them. Lapidary-made beads are recoved from many ancient sources, and in modern times are made in China, Southeast Asia, West Africa, and México.
Drawn Glass Beads
A drawn bead is fundamentally a piece taken from a long tube of glass, that is refined and sometimes altered via certain practices. In order to make drawn beads, it is first required that a “cane” be made. Glassworkers take advantage of the great ductility of glass by creating a mass of glass (a “gether”) with a bubble of air in its interior, and pulling this construction from opposite ends to stretch it into a long cylinder with a central hollow. A cane.
Once canes are formed and cooled, they are divided into handy lengths, and later divided into bead-pieces. This may require cold division (controled fracturing) or hot division (hot-pinching). Although make drawn constructions were devised in quite early glassmaking times, they were not exploited for comon beadmaking until near the Roman Period—and continuously since that time. The canes used for drawn beads may be monochome or polychrome/compound, may have external decorations as well as internal layers of color, sometimes include gold leaf, may be twisted or not, and may have a variety of external shapes (round, square, triangular, etc.); and they greatly vary in size, from quite small to very large.
Once beads are derived from canes, the beads may be finished via any of a number of techniques. Drawn beads seem to date from Roman or even pre-Roman times (in Western Asia), but were made at India just as early. It is not clear whether one industry was influenced by the other or not. In any event, it is a useful and variable technique that, once devised, changed the nature of glass-beadmking profoundly, making mass quantities of similar beads possible in considerably fewer man-hours of labor.
From antiquity, the drawn beads that attract the most attention are the “gold-glass” beads than have gold foil sandwiched between two layers of clear glass (made via the hot-pinched method), as well as wavy “gold-band” beads, made in Egypt and other locations. Drawn beads were made through the Islamic Period, and were improved and elaborated by modern beadmakers as well.
Blown Glass Beads?
We have come to think of “glass blowing” as being synonymous with any glassworking. However, the blowing of glass was only devised close to Roman times (meaning a lot of glass was made prior to this development), and there are rather few beads that were made by this technique—at least until modern apparatus existed to facilitate such work. There are some exceptions from antiquity, as well as blown items that are passed-off as “beads” when they are or may actually be recycled miniature vessels. Also, some drawn beads have thin walls, and are noticeably hollow, leading to the false conclusion that the beads have been “blown.” This is an easy error to make, but we have learned to distinguish some of the finer points of identification, and hope to avoid such errors..
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