r/BeAmazed • u/freudian_nipps • Aug 25 '26

Nature This massive Amethyst geode

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u/NikolitRistissa Aug 26 '26

They form in cavities within the bedrock. Geodes can be as large as this, but they can also be as small as cavities caused by gas bubbles in igneous rocks.

They’re essentially just cavities where the surrounding rock solidifies, dissolved silicates or carbonates are deposited on the surfaces, and eventually grow into crystals. Groundwater or hydrothermal solutions for example, bring in more minerals and they continue to grow.

As for this specific piece, no idea. Geodes can be found all over the world though.