Glass bead

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Selection of modern glass beads
Above right: Various historical glass pearl necklaces from an Alemannic row grave field of the 6th / 7th centuries. Century
Sample card of Venetian glass beads from 1892 in the MEK's permanent exhibition .

The glass bead is one of the oldest pieces of jewelry known to man. They represent the most important artificial pearls . In addition to the simple prehistoric specimens, there is a very broad and varied spectrum of pearls from the epochs of early history .

Beginnings

The oldest glass beads can be found in Egypt during the predynastic period, but were probably faience beads that were burned to glass at too high a temperature. Glass production may have been developed in different places of the Fertile Crescent , for example glass beads from the 25th century BC were found. In Judeidah , Gebelein , Tell Asmar , Jericho , Shahr-i Sukhta and Abydos . Glass beads from around 1900 BC Was found in Tel Dan . No later than the 14th century BC. There was a trade in glass beads between Scandinavia and Mesopotamia .

Beginnings in Europe

There is evidence of a local glass deposit in France from 2000 BC. BC, probably as a by-product of copper production. From the middle Bronze Age 1500 BC. An occurrence from Great Britain is known. From 1400 BC There were probably glass beads produced in Europe, but only in one color and in small quantities. They are predominantly opaque (opaque) and monochrome (one color) colored blue or green (connection to copper). The earliest known production in Europe took place in the Mycenaean workshop in Tiryns from around 1300–1200 BC. Instead of. From around 1200 BC Glass beads were found more frequently and in a greater variety of shapes and patterns, such as pile-dwelling beads , nub beads or eye beads . The production method was aimed at mass. At that time, pearls were probably no longer traded as individual pieces, but in whole strings. The two-colored pearls of this time are always blue, blue-green, green, purple, brown or black (i.e. dark) with a light glass coating (white or yellow).

Pigments , which are usually made from oxides that are produced as waste products during metal processing , provided the color . In addition, the early historical pearl makers were already familiar with the effects of reducing and oxidizing melt atmospheres. They were used to influence the coloring, so the use of iron (III) and iron (II) oxides produced completely different results in terms of color.

This complex chemical knowledge sheds a completely different light on the Merovingians, whose simple and, according to today's view, partly inferior pearls were ignored by research for a long time.

The imperfect surface of some of the prehistoric pearls can usually be explained by the use of too much pigment. Pearls of the same age, the surface of which seems to have remained unchanged and - based on the optics - could also have been produced recently, have a higher proportion of glass matrix.

From this fact alone, and from the fact that many pearls even in a regionally bundled unit such as a burial ground or an individual grave of a necropolis , have strong differences in quality due to different contents of glass matrix, it can be concluded that pearls were not centrally produced, but in many local and regional workshops, which, however, have so far been difficult to prove archaeologically .

More recently, Murano is particularly famous for the manufacture of glass beads.

technology

For the production of glass beads there are different techniques for different determinations and quantities and different elaborate configurations.

Example of processing glass beads: animal figures made of glass beads and wire (from South Africa )

Large, brightly colored glass beads, such as marcasite beads or coiled beads , which went to Basra as barter items and to Palestine as rosaries and which are still an important trade item today, are products of glass blowing in front of the lamp. For wound pearls, a viscous glass mass is usually wound around a metal rod and the pearl is formed by turning the rod. After a short cooling phase, the glass bead is stripped from the rod and placed in a bed of sand for final cooling. The opening in which the metal rod was inserted serves as a hole for threading the pearl.

In the Fichtel Mountains and in Bohemia, the Paterln is made by taking out a portion of liquid glass with conical, tapering iron rods covered with clay and forming the pearl, which is sanded off, polished and covered with threads of different colored glass. They were also exported to Africa as jewelry; these fathers were called negro money .

A common technique for making larger quantities of simpler (e.g. embroidery) beads is to stretch the glass into thin tubes that are cut into small pieces with scissors. These are either used directly (melting) or need to be rounded off. They are mixed with a slightly moistened mixture of lime and coal powder to fill the cavities and heated with sand and coal powder in rotating cylinders until the sharp edges are rounded. After cooling, the pearls are sifted, sorted, ground by shaking with sand, sieved and polished by shaking with bran .

Millefiori beads, Murano, 1920s

The time of the Merovingians knew not only a large number of simple pearls but also particularly complex specimens, the so-called Millefiori pearls (thousand flowers). In this technique, the pearl is composed of several elements, the creation of which is described in different ways. The desired pattern is formed from different colored glass masses. A thin glass thread of the desired thickness is drawn from the hot, still soft glass mass, the cross-section of which still has the - but now reduced - pattern. From this rod, small plates are cut which - placed next to each other - will result in the pattern of the pearl. The platelets are heated so that they form a bond with one another, and the glass, which is still malleable, is wrapped around a rod to obtain a thread hole and melted together.

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

literature

Individual evidence

  1. ↑ Axel von Saldern : Antique glass . In: Handbook of Archeology . tape 7 . CH Beck, Munich 2004, ISBN 978-3-406-51994-9 , pp. 6 ( limited preview in Google Book search).
  2. Jump up ↑ Jeanette Varberg, Bernard Gratuze, Flemming Kaul: Between Egypt, Mesopotamia and Scandinavia: Late Bronze Age glass beads found in Denmark . In: Elsevier (Ed.): Journal of Archaeological Science . tape 54 , 2015, p. 171, 174 , doi : 10.1016 / j.jas.2014.11.036 (English, article online at Academia.edu ).
  3. ↑ M. Panagiotaki, L. Papazoglou-Manioudaki, G. Chatzi-Spiliopoulou, E. Andreopoulou-Mangou, Y. Maniatis, MS Tite, A. Shortland: A glass workshop at the Mycenaean citadel of Tiryns in Greece . In: Association Internationale pour l'Histoire du Verre (ed.): Annales du 16e Congrès . 2004, p. 16 (English, online at aihv.org (PDF; 1.47 MB)).
  4. ↑ Stephanie Mildner, Ulrich Schüssler, Frank Falkenstein, Helene Brätz: Bronze Age Glass in Western Central Europe - Finds, Composition and the Question of its Origin . In: Bianka Nessel, Immo Heske, Dirk Brandherm (ed.): Resources and raw materials in the Bronze Age: Use - Distribution - Control (work reports on the preservation of monuments in Brandenburg) . tape 26 . Brandenburg State Office for Monument Preservation, 2014, ISBN 978-3-910011-75-5 , p. 100–108 ( online on the website of the University of Würzburg (PDF; 616 kB)).
  5. ↑ Arts + Crafts. Volume 30, 1986, p. 268. - Hans Watzlik: The Leturner Hut. Berlin 1932, quoted from the Augsburg 1963 edition, p. 23. Also in: Josef Blau: The glass makers in the Bohemian and Bavarian Forests in folklore and cultural history. Kallmünz / Regensburg 1954, p. 11 (= contributions to folk research . Published by the Bavarian State Office for Folklore in Munich, Volume 8). - Herbert Achternbusch: The hour of death. Frankfurt am Main 1975, ISBN 3-518-02004-8 , p. 35.

Web links

Commons : Glass Beads  - Collection of Images
Wiktionary: Glasperle  - explanations of meanings, word origins, synonyms, translations