Earlier tonight I noticed this image on Facebook. It came with no provenance aside from somewhere in Oregon. It also came with no photographer attribution. Having once owned a smaller specimen of this type of Oregon opal gemstone material shaped into an egg, I know this specimen likewise came from Opal Butte, Oregon, in the northeastern quadrant of the state. Above one can see part of the thunderegg outer shell at bottom right. Photo courtesy of Amazing Geologist on Facebook (all rights reserved).