How are African Glass Beads Polished?
The hub of glass bead production for over four centuries; Africa has become affiliated with the manufacture of some of the most stunning Trade Beads and Fancy Powderglass Beads in the world. Nowadays, Ghana and Ethiopia are the main producers of Recycled Glass Beads, and while countries such as Italy have refined glass-making practices considerably since the 18th Century – the methods used within Africa have remained largely unchanged since that time.
Whether your eyes are drawn to the lacquer-like sheen of our stunning Mali Wedding Beads here at The Bead Chest, or the subtle sheen of Venetian Trade Beads – all have one thing in common. They are polished to such a high degree that even after centuries of age, wear, use and exchange they have not lost that shiny porcelain-like facade that adds to their character.
But how did African tribes-people polish their beads?
Glass in it's molten state is known as a viscous liquid, and due to its compound properties, requires a significant period of controlled cooling – known as annealing. Being the fragile compound it is, glass tends to have a significantly weaker core than exterior when taken out of the kiln. For this reason, it must be “heat-soaked” at a consistent temperature after being fired within a kiln. The process of annealing causes the core to relax, eliminating the possibility of cracking or shattering. In Africa this is generally done as the kiln cools, or by a process known as flame-working. Because the bead's exterior is reheated, it influences the exterior properties and causes the glass to take on the appearance of hot wet wax (clear, with a sheen). As the exterior gradually cools, the sheen is intensified by external influences such as oxygen.
The more traditional method of polishing is still carried out today within the Ghanaian production of Recycled Glass Beads. Have you noticed how our Fancy Powderglass Krobo Beads have a distinctly glossy surface? This is created post-cooling, once beads have been gently eased from their clay moulds. In a similar process to gemstone tumbling, glass beads are refined, shaped and polished using a combination of sand, water and manipulated erosion to the surface by rubbing.
Depending upon the desired effect, Recycled Glass Beads can be gently rubbed against a flat matt stone or sand of fine consistency until any rough characteristics are worn away. They are then polished up using a simple sodium/ sand and water solution. Some Krobo tribes opt to use a resin for polishing, obtained from the native Copafeira tree. With similar properties to amber, the resin hardens post-application and is then rubbed to a gloss-like sheen. Other substances with recognized properties for polishing include beeswax, nut oil and very rarely, palm oil.
Nowadays we celebrate the authenticity of African Glass Beads by leaving them as is, with the dirt and dust of centuries intact. Despite this, the majority of Antique Trade Beads still bear a profound sheen which hasn't been compromised by wear or age. Why not see for yourself? Our Krobo Fancy Powderglass Beads are exemplary of those polished to a stunning finish!