Mar 5, 2025 · Get to know the different types of geodes and what make each of them unique. You'll be amazed at the rich variety of this seemingly ordinary rock on the outside.

A geode (/ ˈ dʒ iː. oʊ d /; from Ancient Greek γεώδης (geṓdēs) ' earthlike ') is a geological secondary formation within sedimentary and volcanic rocks. Geodes are hollow, vaguely spherical rocks, in which masses of mineral matter (which may include crystals) are secluded.

Jan 12, 2024 · If you’re an avid rock collector or simply enjoy unique natural wonders, you may have stumbled upon geodes. Geodes are fascinating rocks that contain hollow cavities filled with crystals, minerals, or other materials but being able to …

Jan 2, 2023 · Believe it or not, some geodes grow just that big! Brazilian amethyst vugs the size of small hot tubs have on display at the Quartzsite and Tuscon rock extravaganzas. But these are still babies compared to supersized cavities lined with supersized crystals.

Geodes are spherical rock structures with an internal cavity that is often lined with quartz crystals and banded agate. Some are lined with more mundane or spectacular materials.

Two geodes lay claim to be the world's largest: a massive, 35-foot wide celestite geode in Ohio and the 30-foot long, selenite-lined Pulpi Geode in Spain. Depending on how you want to measure size, either one could be considered the largest.

Sep 5, 2023 · The inside of the geode is about 35 feet in diameter at its widest point, is 12,000 to 16,000 years old and is made of almost pure celestite. Some to the largest crystals are as large as three feet long!

Jan 13, 2021 · Mineral purveyor Nowar Minerals, Inc., shares photos of massive amethyst geodes that are almost too incredible to be true. (But they are.) Some of the rocks weigh more than 10,000 pounds, and one gigantic piece clocked in at a staggering 26,000 pounds and 22 feet tall.

Aug 25, 2022 · Geodes require hollow spaces in rock where mineral-rich water can slowly deposit crystals on the interior surface. As more crystals grow, they make the open space larger. Geodes form in volcanic rocks or animal burrows, beginning as bubbles, mud balls, or tree roots in sedimentary rocks.

Check out our large geode selection for the very best in unique or custom, handmade pieces from our rocks & geodes shops.