Description

Geodes are geological rock formations which occur in sedimentary and certain volcanic rocks.  They are essentially rock cavities or vugs with internal Crystal formations or concentric banding.  The exterior is generally Limestone while the interior contains Quartz Crystals and/or Chalcedony deposits.  If the Geode is completely filled with Crystal, being solid all the way through, it is then called a nodule.

Rhyolite is an igneous, volcanic rock that is composed of Felsic, or Silicate minerals such as Silica, Aluminum, Sodium and Potassium. This material, also called Volcanic Tuft and Rainbow Rock actually began as volcanic ash spewed from the mouth of a volcano millions of years ago. This ash was exposed to heat and pressure that resulted in turning it to stone. The bright banded colors are a result of exposure to high concentrations of iron oxides. The material is similar to that of Granite, Pumice and Obsidian but due to the cooling process when formed, Rhyolite did not form any crystals, thus changing the texture of the material.