Using cutting-edge techniques, the Göttingen team discovered that the crystals form at much lower temperatures than ...

The crystal columns at Pulpí are made of gypsum — the product of water, calcium sulfate, and lots and lots of time — but not much else has been revealed about them since the geode's ...

Background. Geodes are hollow rock formations that often contain crystals or mineral matter, and they are formed through various geological processes, including volcanic activity, sedimentation ...

Colossal crystals, gigantic geodes: Selling ‘mind-boggling’ collection no easy task Originally published February 27, 2016 at 8:00 am Updated February 27, 2016 at 12:48 pm ...

Crystals found in pockets of volcanic rock likely formed at low temperature . ... Researchers studying amethyst geode formation in Brazil’s lava flows have proposed temperatures below 100 °C.

Amethyst geodes in Uruguay have been found in cooled lava flows, which date from the original breakup of the supercontinent Gondwana around 134 million years ago. However, their formation has ...