Glass Beads
Technical methods for the bead-making are different not only according to material, but also according to the state of material during the process of manufacture. Semple distinguishes three states of glass: firstly, as a very hard, brittle and solid subst
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Glass Beads
6.1
Section I: Manufacture of Glass Beads1
Technical methods for the bead-making are different not only according to material, but also according to the state of material during the process of manufacture. Semple distinguishes three states of glass: firstly, as a very hard, brittle and solid substance, which, like stone, can be cut into any form by cutting instruments; secondly, as a liquid substance, which, like molten metal, can be cast; and thirdly, as a soft, very plastic, tenacious and ductile substance, which, after cooling off, will retain unchanged the form which it obtains in the soft state.2 Most glass beads were made neither in a solid state nor in a liquid state, but in a viscid one. As a viscid substance, glass is able to stick together (tenacious), capable of being drawn out into wire (ductile) and fashionable into any form by moulding or modelling (plastic) and may be blown into a hollowness.3 Glass objects, including beads, could be regularly manufactured only when people realized and duly took advantage of some of these properties of glass. This is perhaps the main reason why its regular production on a large scale only dates from the New Kingdom in spite of early invention of the process of glazing. The chief methods of manufacture of glass beads are as follows: 1. Modelling Method. By taking advantage of its plasticity, glass was rolled into a ball or cylinder, or pressed into a bar, or modelled into various shapes by some instrument. The perforation was obtained either by piercing a hole through the solid bead when reheated or by drilling when cold. The surface of this kind of glass beads is often rather dull. This method was rarely
1 Beck, Classification, pp. 60–62. (All the references given immediately after the heading of a section are the general ones which are freely utilized in the text of that section, usually without any particular indication or footnote.) 2 Kisa, Das Glas im Altertume, p. 259. 3 Dillon, glass, p. 7.
employed. But beads made at first by other methods might be retouched afterwards so that traces of their manufacture were erased, and thus, they may be easily mistaken for beads made entirely by modelling. 2. Folding Method A. By taking advantage of its flexibility and tenacity, glass can be made into a bead by folding. A small strip of glass was bent over to make both ends meet, which would be fused together either by themselves when they were sufficiently hot or by slightly reheating. It could be further shaped into any particular form by modelling with some instrument. Beads made by this method usually still show the trace of the junction. 3. Folding Method B. Another method was to prepare a slab of glass roughly round. While it was still plastic, a rod was pressed through the centre of it perpendicularly to the face, and then, the whole edge of the slab was folded up so as to join together and enclose within it the rod which would be withdrawn later on. Beck mentions a similar method, which, however, started with a slab of glass roughly square and ended
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