These beads are the real deal.

In the 60s there was an international vogue for precolumbian artifacts, and tons of antiques, including beads, starting moving out of Mexico and other Latin American countries. Very few came from documented archeological digs; most came from huaqueros, unauthorized excavators who sold their finds for cash. Most of the beads you see on the market today were bought by North American collectors during that period.

Artifacts coming from Guerrero, Mexico -- which is where these beads originate -- were attributed to "Mexcala culture," believed to have thrived in the area of the Mexcala river from 700 AD - 650 BC. However, there was almost no archeological study of the area before it was picked over by huaqueros, so it's unclear which Guerrero artifacts actually came out of the ground and which were manufactured by the contemporary descendants of the Mexcala people to be sold as "antiquities." Modern artifact manufacturers were very skilled, and it's impossible to date stone scientifically. It's possible that most of what is known of the Mexcala is fictional, based on forgeries; we'll never know for sure.

The stones used are all called "jade" bc precolumbian cultures didn't distinguish between different types of green stone: diorite, serpentine, emerald etc were all considered "jade." Incidentally, Chinese culture had similar attitudes towards green stones, which is why nephrite and jadeite are both considered "jade" today.

These are quite lovely. It's a good find. I wear mine all the time.