Geodes

Im sure we’ve all heard of geodes before, and many of us have seen them before too, but have you ever wondered how they form? What kinds of geodes are there? This report is intended to tell you just that.

Telling you what geodes are is probably a good idea first. Geodes are, by definition, spherical, hollow rocks that contain crystalline structures varying in size, shape and color. The color usually comes from impurities in the crystals while they’re forming. Most geodes have a fine grained quartz outer layer. This layer is important because without it, the crystals inside would not withstand the weathering process. Some geodes are surrounded by a mineral high enough on the Moh’s scale that this layer isn’t necessary.

Geodes are believed to be formed in 2 different ways and are classified into one of these 2 groups: Igneous geodes, that form in hardened lava flows in cavities created by air gaps, and sedimentary geodes, that form in spaces formed by roots, decomposed animals, abandoned burrows, Ect. Over time, mineral rich water will soak in these spaces and leave behind  silica deposits. Eventually these deposits form the hexagonal crystals so commonly found in geodes. This is one of many theories about sedimentary geodes. In both Igneous and sedimentary geodes, the process in which the crystals build up inside happens over the course of about 200 million years.

As mentioned above, geodes are separated into groups, but There are many other ways to group up geodes. There are many ways to group geodes like location, or by the formation, like a geode in which the crystals inside grow into a solid form is called a nodule. one could classify geodes based upon what’s inside them, but there are so many possibilities, there would be a lot of groups. The most commonly found mineral is quartz and agate. Also possible is onyx, jasper, celestite and amethyst. There are also many more that can be found.

Geodes are considered a mystery by scientists. We don’t know exactly how they form, and can only theorize, just like you never know what’s inside one until you open it. Kind of like everything else when you think about it. We might never know how exactly geodes form in this lifetime, and there’s probably still many more kinds to be discovered.