This is a set of small Dugway geodes which all have natural breaks which occurred underground and these specimen come from the Dugway Geode Beds in Utah. This Dugway geode set is made up of small specimens with the largest geode measuring 2.17 inches long by 1.69 inches wide and the smallest geode measuring 1.59 inches long by 1.15 inches wide. 

Dugway geodes began their creation 6-8 million years ago when volcanic activity occurred in Western Utah and deposited rhyolite which is an igneous rock over a very large area. Over time the trapped volcanic gases formed cavities in the rhyolite layers and millions of years worth of mineral rich ground water and hydrothermal fluids circulating through the rhyolite lead to the minerals being slowly deposited into the cavities where they grew into solid forms. Each geode is unique in its composition. Geodes range from being completely hollow to being completely filled with chalcedony and different quartz formations mostly of the druzy variety and can show in various colors. The next stage in these geodes creation story begin sometime around 30,000 and 13,000 years ago when Lake Bonneville formed fed by glacial melt water it eventually covered much of what is now Western Utah and when at its highest level had a depth of 1000 feet and extended into present-day Idaho and Nevada. Lake Bonneville fluctuating water heights known as transgressive phases, regressive phases and the lake even had an overflow phase combined with wave motion activity lead to the erosion of the rhyolite in turn essentially washing out the spherical geodes and carrying them several miles away from where they 'grew' to be deposited at a new location. Now these geodes reside on the edge of the salt flats at what is now called the Dugway Geode Beds which is near the town of Dugway and the Dugway Proving Grounds in Juab County, Utah. This Dugway geode set would be an excellent addition to any rock and mineral collection. I combine shipping on multiple buys so be sure to check out my eBay store Mountainamma's Marketplace where I have thousands of items to browse. For buyers of multiple items please message me before you buy for help combining shipping fees.