Discernible differences were noted even back in the 1971 Arizona Highways article (altho the author was unable state exactly what these differences were).

What seems unlikely to me is that existing beads pre-date the 19th century, and the mid- to late-19th century at that.

The notion that the "padre" beads in the American Southwest were distributed in the 16th and 17th centuries by the Spanish conquistadors and friars seems a real stretch.

The import of Chinese beads, however, still seems to be an open question to me, especially in the Pacific Northwest.