Many beads are a challenge because of their intricate decoration or tiny size. This one is more difficult to replicate, because of its large size and multi-colored core, and the deceptive applied trail.
It was found in excavations at Hen Gastell, Neath, Wales This site was excavated in advance of road and bridge construction in 1991-92. There was found evidence for a high status occupation from the 6th to 10th centuries, with subsequent reoccupation in the later 12th century. The finds are not in relation to graves, however. That is unfortunate, as it means the estimated date for the bead is larger than it would be in a complete grave context.
The vibrant photo above comes from the Gathering the Jewels, and is held at the Neath Museum. (I’m not sure if that museum ever reopened.) They give it a 8th to 10th C date, but unfortunately, don’t list a size.
Luckily, Medieval Archaeology at the Archaeology Data Service has a report on the excavations. The portion of the article about the bead was written by Ewan Campbell, and has the following to say about it:
About one-third of a very large annular bead of D-shaped section ornamented with raised cable decoration. The body is of mixed glass types wound around the central core, the colours used being pale green, cobalt blue, wine red, and opaque blue, though the exterior appears mainly dark blue. The cable ornament consists of an equatorial band crossed by V-shaped elements with a “knot” at the cross-over point. The cable is mainly of opaque yellow twisted with and opaque brown which close inspection shows to be formed from finely mixed strands of opaque white and purple-brown glass. Estimated original diameter c. 35mm, Height 17mm, hole diameter 10mm. String beads … are characterized by the use of applied trails of twisted bichrome glass rods. The beads are an Irish type, mainly found in Hiberno-Norse contexts and Scandinavia. This bead is unusual in having an annular form rather than the more normal tripartite barrel-shaped form, in the use of opaque yellow rather than blue and white, and is of exceptionally large size. The type is usually dated to the 9th to 10th centuries on the basis of occurrences in Viking graves, but there are few from other reliable dated contests and grave finds are often old when buried. The use of bichrome twisted rods, especially using opaque yellow, is also characteristic of beads on the 6th to 7th centuries in Anglo-Saxon contexts and in glass vessels of the 8th to 9th centuries and there is no reason why beads utilizing the same rods would not be of the same date. The construction of the body of the bead is of interest as it shows the use of a number of different colours of class, including deep blue, wound together. This raises the possibility that the bead was manufactured on site using the glass sherds described above. However, the use of wine red glass in the bead suggests that it is of at least 8th century date, later than the Hen Gastell glass and most of that from Celtic sites. – Campbell
The first challenge is the hole diameter of 10mm – much more than a standard mandrel size. While you can get larger metal rods from the hardware store, the larger mass will require more preheating. The brass and mild steel rods I tried were very, very effective at transferring heat down to my fingers. So either a specialty tool , or a protective handle will be a good idea. The larger size might require a larger flame to keep it all at a working temperature. I’m not sure if my hot head is up to the challenge. The total bead size is 35mm – that’s a lot larger than many beads.
Second challenge is the different layers of glass. On one hand, this is a beautiful opportunity to use up some leftover bits of glass – the colors noted were “pale green, cobalt blue, wine red, and opaque blue” giving a final outside impression of dark blue. Of the other hand, each layer of glass you wind on will give you another opportunity to make an error, and leave a fault line for later breakage. Be very careful all the glass has the same COE (coefficient of expansion ) or this is doomed to break when you least desire it.
The final challenge is the twisted bi-chrome rod. You could settle, and just use yellow and brown. But if you accept the full challenge, you must first make a twisted rod of opaque white and purple-brown, twisted tightly and drawn out smaller. By measuring the archaeological drawing, I estimate that the twisted bi-chrome rod is approx 2 mm wide when applied on the bead, and it appears there is twice as much yellow as the white/purple-brown. Getting that color balance right, and then making a finished rod of 2mm size will take some trial and error.
Finishing up, the V-shaped trails are each approx 15-20mm long, measured from the knot. Based on the size of the fragment, and the normal Irish, multiples of three, decoration style, there are probably 3 of the v-shaped trail motifs surrounding the bead.
Excavations at Hen Gastell, Briton Ferry, West Glamorgan, 1991-92. By P.F. Wilkinson with contributions by E. Campbell, et al. Medieval Archaeology, vol 39 ( 1995) pp. 1-50.