Forbes contributors publish independent expert analyses and insights. David Bressan is a geologist who covers curiosities about Earth. Discovered in 1999 during mining operations in the Mina Rica (the ...

Boulder, Colo., USA: The geode of Pulpí is an 11-meter hollow ovoid with crystal-paneled walls. It is like those familiar couplets of stone interiors covered with bright crystallites, but so large ...

How World's Largest Geode Grew to Half Size of Small Room | RealClearScienceMost geodes—hollow, crystal-lined rocks—can fit in the palm of your hand. But the giant Pulpí Geode, which is about half the ...

Any geode might make us wonder: What geologic forces form these hollows lined with crystals? But the Pulpí Geode, discovered in an abandoned Spanish mine, takes wonder to a different scale. One of the ...

The development of plans for a large geode was clearly the most challenging assignment for McNamara Alumni Center's structural engineers, Minneapolis-based Meyer, Borgman and Johnson (MBJ). The ...

Most geodes—hollow, crystal-lined rocks—can fit in the palm of your hand. But the giant Pulpí Geode, which is about half the size of a small bedroom, fills part of an abandoned mine in southeastern ...