this is a great bead Thomas and it appears to be well worn and treasured. I love beads like this. I have one that I would not sell, it is as Danny would say, an 'old dog'. If Danny reads this post I'm wondering if you can identify the material. The blueish green part is transluscent and has a high sheen that I've tried to show in the first picture. It measures 34mm x 28mm. It was found in Mali.