Tribal stone statement necklace

Tribal statement necklace. The metal part is silver tone and I’m honestly just not sure what that stone is in the middle. It’s a very stunning necklace that was my Grandmother’s. She traveled extensively and I imagine she got this on one of her voyages. Please see all pics. There is a small chip on the stone... nothing that I even could see at first I felt it then had to look for it. Smoke free home. Next day shipping.