Glass beadmaking

The glass bead is one of the oldest pieces of jewelry of mankind. You are the most important artificial pearl dar. In addition to the simple prehistoric specimens, there is a very wide and diverse range of beads from the eras of early history.

History

Common type of prehistoric pearl is the monochrome ( single color ), opaque ( opaque ) pearl, usually in shades of blue, yellow, brown or orange. Color-giving pigments were prepared, as a rule of oxides which are formed as waste products of metal processing. In addition, the prehistoric beads makers the effect of reducing and oxidizing atmospheres melting was already known. And iron ( II ) oxides color completely different results achieved - they have been used to affect the color, as by the use of iron ( III).

These complex chemical knowledge throw a completely different light on the Merovingians, whose simple and in today's opinion partly inferior beads were long time no attention from the research.

The imperfect surface of a part of the early historical pearls can usually be explained by the use of too much pigment. Brunette beads, the surface of which appears without a change, and - on the basis of the optical - could have been produced in recent times, have a higher content of the glass matrix.

Alone from this fact, and the fact that many beads in a regionally focused unit as a burial ground or a single grave of a necropolis, strong differences in quality, due to different levels of glass matrix have, can, be concluded that beads were not produced centrally, but in many local and regional workshops, but so far can be difficult to detect archaeologically.

From today particularly Murano is famous for the production of glass beads.

Technology

For the production of glass beads, there are different techniques for different provisions and different numbers and complex configurations.

Large, colorful colored glass beads as the Markasitperlen or lampwork beads, which were, among others, as an exchange item to Basra and as rosaries to Palestine and still form an important article of commerce, products of glass blowing in front of the lamp. For wound beads a viscous glass mass is wrapped around a metal rod and shaped by rotating the rod, the pearl in the rule. After a short cooling the glass bead is stripped from the bar and put the final cooling in a sand bed. The opening, in which put the metal rod is used as a hole for threading the bead.

Im Fichtelgebirge and Bohemia to craft the Paterln by with conical, pointed and covered with clay iron bars a serving of liquid glass takes out and it forms the pearl, which sanded square, polished, is also well covered with threads of different colored glass. They were exported as jewelry to Africa; these were called Negroes Paterln money.

In a common technique for the production of large quantities of simpler (eg nitrogen ) beads, the glass is drawn out to form thin tubes which are cut with scissors into small pieces. These are either used directly ( melting) or even require rounding. They mixed this with a slightly damp mixture of limestone and coal powder to fill the hollows, and heats it up with sand and carbon powders in rotating cylinders until round off the sharp edges. After cooling, the beads are sifted, sorted, ground by shaking with sand, sieved and polished by shaking with bran.

The Merovingian knows in addition to a variety of simple pearls also particularly complex specimens, the so-called Millefiori beads ( thousand flowers). In this technique, the pearl of several elements is composed, their formation is described differently. The desired pattern is formed of different colored glass masses. From the hot, still soft glass mass, a thin glass thread is pulled in the desired thickness, the cross section still - has patterns - but now reduced. For this rod plates are cut, the - placed together - the pattern of the pearl will arise. The flakes are heated so that they together form a bond, and the still malleable glass is wound around a rod to obtain a thread hole and melted together.

If the pearl keep a rod-like structure or a polygonal base shape, it is through processing ( such as pressing on the work surface ) brought into this form.