Without seeing the beads nobody will be able to tell you what they
are. All sorts of material is cut in Africa, and elsewhere as well.
They could be anything from glass, howelite, stained bone,
reconstituted turquoise to plastic!
Can you post up a picture on a website?
Can you give us their specific gravity or refractive index?
You refer to African Turquoise. Have a look at the picture on the
pages at http://www.accentsbeadshop-md.com/ (I’m not connected with
them.) They may help you make a judgment - but no gemologist worth
their salt will be able to help you unless you can take some