Ancient Earth Trading Co. - (866) 327-8401

88 mm Opal Mountain Geode Rhyolite Sphere

More Views

88 mm Opal Mountain Geode Rhyolite Sphere

Availability: Out of stock

Opal Mountain Rhyolite

Opal Mountain, Idaho, USA

Sphere Diameter : 88 mm
1 inch = 2.54 cm = 25.4 mm

Looks planetary with all of those opal thundereggs showing!

With extreme care, this delicate opal filled material has been, painstakingly, polished to a mirror finish!

This piece has hundreds (or more!) of geodes on the face with common and precious opal, you'll see precious opal flashes as you turn the sphere round, very hard to capture in a photo. One very large geode is also shown.

We collected this material and hand selected each for its patterns and unique coloring. Every orb you see on the face of the sphere is filled with precious or common opal.

Each of our spheres is perfectly round with no pitting, cracking, or excessive use of glue to hide imperfections.


Opal Mountain Rhyolite is found from a single source deposit in Idaho.

6-4 million years ago, volcanic activity left rhyolite and perlite ash deposits with gas pockets (aka a thunderegg). Before and during our last Ice Age, roughly 1 million to 50,000 years ago, geysers seeped mineral (silica) rich solution up and through the ancient volcanic deposits and slowly filled the cavities left by the gas pockets with a combonation of both precious and common opal.