Glass trade beads salvaged from the wreck of a Spanish ship sunk in 1747 on the Yucatan peninsula. The beads were pressed in a mold, are faceted to resemble precious stones and would have been suitable for mounting. A professor at the local university was involved in the archeological dig. He collected glass with natural iridescence. Dug a 145 American that was iridized and was able to make a trade for some of the beads. Would have made a better story to have traded a Manhattan for some glass beads.