This dropped off a Dust Elemental in Stygia Delta while I was looking for blazing scarabs north of the river near Inarus. Maybe they drop off Goo Elementals, too.
There are small scarabs that are grey most times in this same area that are not valid for the glass quest Curse of the Scarab (Level 50), but sometimes blazing scarabs spawn in their place that are yellow. I couldn't determine the reason.
Edited, Feb 28th 2014 1:17pm by ZontasHierospirit