The amethyst geodes, of rare beauty, form in volcanic rock cavities. How did these purple crystals emerge millions of years ...

Researchers have revealed the geological processes behind the formation of amethyst and agate geodes in Northern Uruguay’s Los Catalanes District, offering new insights into mineral composition ...

Mystery of Uruguay's amethyst geodes: New model to explain amethyst formation. ScienceDaily . Retrieved June 2, 2025 from www.sciencedaily.com / releases / 2024 / 10 / 241002135231.htm ...

Researchers studying amethyst geode formation in Brazil’s lava flows have proposed temperatures below 100 °C. The new study uses similar techniques and includes an additional oxygen isotope.

The results show that the amethyst geodes were formed at temperatures between 15 and 60°C (59°F and 140°F) – a surprisingly low temperature, the researchers say. This suggests the amethyst ...

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 ...