Hi, the lampworked beads in your necklace are quite similar to some of the beads in the Pietro Bigaglia sample book kept in the Glass Museum of Murano, dated about 1840-1860; some of them are also in the Giacomuzzi sample book (see Karl Karklins, 2002 "the Giacomuzzi bead sample book and folders" in Beads, Vol.14)dated about 1852-1868.
Ciao,
Giorgio

Noting that vol. 14 of "Beads" is available for just 7.50 at this time, as posted in another thread...

South America has always seemed to have recieved a large quanity of unusual bead types never found or only found in small quanities in any other area of colonial expansion.The squiggle beads on this necklace for example is what I believe is a revival bead.It was present on the Tredeau site in Louisana in the early 1700's but also found in early to mid 1800's in S, America. There can be no doubt that the extensive variety of beads in South and Central America is directly related to the Catholic Church's use of beads as an enticement for attendance.It seems to me that a lot of this type of necklace are heirloom pieces. Richard