Bisson (2000) thought that because of coppers redness, luminosity and sound, it was valued by Africans. For many African cultures, the redness could be with life giving powers. Bisson (2000) also noted that the redness is a symbol of transition and it association with transition could explain why the wide use of copper in rituals in various African states. Also, its ability to reflect sunlight is suggested represent aggression and liminal boundaries between states, thus emphasizing its transformative properties. Finally, because of coppers use in bells and drums, it is thought to aid in the summoning spirits, when the instruments are played.