At Sumbay SU-3,three obsidian samples were analyzed from excavated contexts and all three turned out to be of the Chivay type(Burger, et al. 1998: 209;Burger, et al. 2000: 278), as shown in SectionX3.4.3X. Two¹⁴C dates were run and returned dates from the early part of the Late Archaic(Ravines 1982: 180-181). One sample was from stratum 3 and it was dated to 6160±120 (BONN-1558; 5400-4750 BCE). Another sample was from above it in stratum 2 and it dated to 5350±90 (BONN-1559; 4350-3980 BCE). One of the three obsidian samples came from Stratum 4 of unit 5, while the other two samples came from higher levels. The Stratum 4 sample probably dates to the Middle Archaic.