Cristobalite in Obsidian

From Milford, Beaver County, Utah. - not the typical locations in California. A ball of cristobalite set in a mass of obsidian. The ball is probably hollow and lined with micro cristobalite crystals. There is an empty cavity on the back side where another ball was at one time. Mounted on an acrylic base with hot glue.

45 x 25 x 15 mm  The ball of Cristobalite is 12mm across.