It is a unique one. IÕve never seen such a bead.
But the color green occurs in beads from the Krobo area. Also the use of small beads as eyes as one of the eyes in your bead. There are also green Akoso beads. The shiny surface occurs too when the heat of the furnace is high enough and no grinding afterwards is used.
Added are two photographs of beads collected in Benin with a black core and shiny surface and just about the same size as yours. The only examples I have. But were in Africa they were made is an enigma to me.
Pity you did not call Amsterdam on your last trip, Hans
PS these two beads are also in the collection of the Picards on internet
the odd thing is, I have found these in association with Ghana powder glass beads and with Mauritanian powder glass beads......any light?
Sorry for the phone image
The air bubbles/impurities in Rosanna's bead appear to follow a circular pattern, around the centre of the bead. To me, this would indicate it is a wound bead, and not a powder glass bead.
I don't know much about beads outside the European trade bead era, but I wondered if this was an ancient stratified eye bead or a very small Hebron.
I don't see any evidence of the granular structure of most powder glass beads.
BTW it was found on a mixed strand of African trade beads.