Obsidian ear spool, which is a pulley type with inner and outer flanges. Obsidian ear spools such as this one demonstrate excellence in lapidary art in Valley of Mexico. These spools are made from one solid piece of obsidian by grinding and polishing. This piece is translucent - it is so thin that light shines through it.

Ear spools of this quality would have been worn by high status individuals  as late as the coming of the Spaniards in the 16th century.