By Michael J. Kallstrom, MS

 

Oh Geode, so plain as to not inspire second thought,

Yet thou intrigue me still with curious wonder,

For wisdom you contain, not easily raught,

That judging without beauty within is blunder.

 

Geodes epitomize the wisdom of not "judg

ing a book by its cover" as they often times appear to be "just a rock" but contain within a beautiful world of crystals and minerals. Despite their less than plain exteriors, thes

e rocks attract many different people for the wondrous treasures they hide within. Forming in both sedimentary and volcanic rocks all over the world, geodes have often been a mystery to the general public despite being widely known. How do such magical rocks form?

 

Well to understand the answer to that question, we must first understand what a geode is. A geode is a rock consisting of a cavity lined with crystals or mineraloid matter. The term geode describes a formation rather than a composition, so you can have geodes of all different shapes and mineral content. For example, amethyst "cathedrals" from Brazil are a specific variety of geode, while Texas has been known to produce ellipsoidal calcite and celestite geodes. Regardless of their origin, shape or what they contain, all geodes form from a similar (although still debated) process.

 

Geodes form, quite simply, by a void filling in with new material out of a fluid. The major difference between sedimentary and volcanic geodes occurs in the first step of this process...cavity formation. In sedimentary geodes, found mostly in limestones and dolostones, a preexisting nodule within the rock gets dissolved away by groundwater, resulting in a void. In the case of volcanogenic geodes, found mostly in deep tuff deposits and lava flows, the cavities form from relic volatile pockets or "bubbles" that became trapped in the volcanic rocks as they cooled quickly. In some cases lava flows, such as those found in Bra

zil, produce pillow basalts and lava tubes. The outer shell of these pillows and tubes insulate lava inside allowing the lava to continue to 

flow leaving behind empty spaces. In all of these instances hydrothermal groundwater flows through surrounding rocks and leaches out key elements necessary for mineral formation. In the case of sedimentary environments, the major element is calcium with varying amounts of strontium, manganese, carbon and sulfur. Volcanic rock

s are generally more silica rich with trace amounts of iron and magnesium. When these highly reactive and chemical-rich fluids fill in the empty cavities and begin to cool slowly the elements bond together to form the magnificent gems that give geodes their allure. Each different fluid that passes through the void deposits a concentric layer of mineralization. In some cases the voids fill in completely with one material or in other cases contain a variety of minerals.

 

Geodes appeal to a wide range of enthusiasts. In some cases the geodes completely fill in with beautiful bands of colorful chalcedony, a variety of cryptocrystalline quartz. This banded chalcedony material is known as agate and is highly sought after by collectors for the unique traits found at each locality throughout the world. Currently Nature's Treasures houses some of the only Island Agate and River Crossing Condor Agate available to the general public in North America. The metaphysical community values geodes for their ability to draw in negativity, contain it and ultimately transform it into positive energy. Some metaphysicians even use geodes as a healing tool to remove negative entities from people and places that remain trapped by the positive energy of the crystals. However, the largest contingency of geode lovers are by far pure-hearted children, and families they belong to. The sheer curiosity and wonderment of what an unbroken geode contains inside can draw out the child from within even the most stone-hearted adult.

 

The unknown world within each geode is much akin to the unknown of new beginnings. Often times we fear the unknown of what is coming and forget to celebrate the beauty of what could be. In order to remember the joy of the New Year, one Nature's Treasures family has established their own annual tradition. For the New Year the parents and children collectively choose an uncracked geode, take it home, and crack it open. To them this is a blessing on the year to come and reminds us to be excited about the treasures our futures hold rather than fear the unknown of it. With the Chinese New Year coming up on February 5th, this is a prime time to break in a new tradition (or geode) and reclaim the beauty within and the joy of each new day.