Black Stone Pendant Mexico Taxco TC-311 925 Silver Setting Square

Unsure of what the stone is, but it is black with small sparkles. Stone is bezel set in a sterling silver setting with pendant attachment. The back of the setting is marked Mexico TC-311 925. Very good used condition, normal wear Measurements: width - 1"; height - 1"; depth - 3/8" Please contact us with any questions. Please feel free to make an offer. Thanks for shopping with us!