Opal from Queretaro, Mexico: Occurrence and Inclusions
An examination of play-of-colour opal from Mexico and its variety of inclusions.
Abstracts; Summer 2009
This article, from the Summer 2009 issue of Gems & Gemmology, is a compilation of abstracts of important gemmology-related articles published outside of Gems & Gemmology.
Chrysoprase and Prase Opal from Haneti, Central Tanzania
Commercial quantities of gem-quality chrysoprase and green prase opal (nickel-bearing chalcedony and common opal, respectively) have been recovered from altered serpentinite deposits near Haneti, Tanzania.