Traditional glass beads of Ghana are often referred to as Krobo beads (the Krobo mountains being the main area of production). These beads are made from recycled glass and have been made this way since the 16th century and used as a form of currency.

"Glass is a melding of the traditional four elements, because through fire and air the silica earth element is made molten and transmuted into a liquid only to return to its earthly state as an apparent solid. It can be made to focus light or allow light to pass through invisibly or carry lightwaves great distances through tiny strands. Metaphysically, glass represents and carries the energies of transformation, merging of elements, rebirth, focus and communication. The colors of the glass bring the vibrations of those specific color energies." See full Glass Meaning at http://meanings.crystalsandjewelry.com/glass/