Heshi necklace

Given to me from my grandmother it’s Navajo heshi of some sort I think but not sure. It looks old and feels of great quality.

any info would be appreciated.

Welcome to Turquoise People! It looks to be olive shell heishi.

Thank you my grandmother gave me a few boxes of older jewelry she labeled old native items and I recall her mentioning Navajo but I was young and pretty uninterested at the time. I recently came across the boxes and being older was a little more interested in what she had given me and decided to do a little digging