Amethyst is a violet variety of quartz that has been used as a gemstone for many centuries and is a key economic resource in northern Uruguay. Geodes are hollow rock formations often with quartz ...

Researchers from the University of Göttingen have investigated an intriguing geological phenomenon in Uruguay. These scientists are trying to uncover the mysteries behind the formation of amethyst ...

Since at least December 2017, a photograph of an impressively tall geode has bounced around the blogophere, almost always credited to a company called Nowar Minerals Inc. and accompanied by the ...