“…This rhyolite obsidian has been identified in archaeological sites by Stern and Porter (1991), Stern and Curry (1995), Stern et al (2002Stern et al ( , 2012, Bellelli et al (2006), Reyes et al (2007) and Cruz et al (2011), and is found in high densities in coastal sites, occupied by groups that utilized canoes to support a marine based economy, located as far as 400 km to the north and south of this source (Stern and Curry, 1995;Stern et al, 2002;Reyes et al, 2007). In these kinds of contexts, Volc an Chait en obsidian occurs in occupational levels as old as 5610 BP (Stern et al, 2002;Stern, 2004a).…”