On a visit to Tucson, relatives took me to a gem and mineral show where we saw a collection of geodes. Ordinary on the outside; beautiful on the inside. Will you please tell us how they are formed and ...

Iowa’s state rock is all over the state’s southeast corner, but to find one you need to know someone. “There’s tons of geodes over here, but nobody has opened it up to the public,” said Kirk ...

Geodes are irresistible. They fill display cases and museums everywhere. I’ve even got one on my desk at home: a smooth, brownish rock encasing milky lavender crystals. It’s hard to deny the allure of ...

Geode is a type of sedimentary and volcanic rock that is hollow, vaguely circular rock, in which masses of mineral matter (which may include crystals) are sequestered. The term 'Geodes' was derived ...

As the saying goes, “There’s gold in them thar hills.” The great thing about Utah is, not only is there gold out there (yes, really, although it’s not all that easy to find) but also geodes, topaz and ...

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 ...

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 ...

Göttingen University researcher Fiorella Arduin Rode working in open pit mine of the study area, Los Catalanes mining district, northern Uruguay. Along with Ametista do Sul in southern Brazil, these ...