Some of the better agates come from the Ochoco Mountains,Up out of Prineville ,Oregon(Part of the Oregon High Desert)
and the Crooked River That drains the region has produced some very rare agates that alot of jewelers would trade their false teeth for.
This is an Iris(not rainbow) Banded Precious Opal that looks like a Ducks Head in the white part.(It helps if you have a few beers to see this )THIS IS VERY NICE,VERY GEMMY AGATE FOR THE PRO'S.HOPE YOU ENJOY THIS RARE TREASURE.
It is about 2 oz and measures 3" x 2" (sort of) and is the standard 5 mm thick.