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Geology: Geodes

Geology: Geodes

Author: Nathan Lampson

This lesson will present how to identify and classify geodes.

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A geode is a rounded, hollow rock that contains mineral crystals.


Formation of a geode:

Water containing dissolved minerals seeps into cracks found between rocks.

Crystallization occurs when the dissolved minerals form organized structures.

The process of crystallization is very slow and geodes take a long time to form.


The kinds of minerals used to form geodes determine their color.

Example: Geodes made of iron look different than geodes made of copper

Geology: Geodes