What Is A Geode Rock

A geode is a rock with a special surprise inside.

What is a geode rock. This celebration of geodes does not stop with iowa. Iowa a state known for its geode deposits has the geode as its state rock officially designated in 1967 and has a state park called geode state park. From the outside a geode looks like an ordinary rock. If a rock like this is broken open however it will reveal a center that is filled with colorful crystals.

Shells tree branches roots and other organic materials often decay away to leave a void for the formation of mineral materials. The only true way to know if a rock is a geode is to crack or cut it open and find out if it contains a crystal core. The crystals are formed by the filling of vesicles in volcanic and sub volcanic rocks by minerals deposited from hydrothermal. Geodes can also be embedded inside another rock layer such as limestone.

In ohio a large geode called crystal cave is open for tours. A geode is a round rock which contains a hollow cavity lined with crystals. This can make geodes hard to precisely identify as whole rocks for the beginner. Except for being kind of roundish there isn t much remarkable or interesting about them.

Some geode rocks are the size of a pea others are the size of a soccer ball or even larger. Geo means earth and these amazing rocks. Geodes in sedimentary rocks are usually found in limestones dolomites and calcareous shale in these deposits a gas filled void can serve as the opening for geode formation. From the exterior a geode appears to be a boring round shaped rock with little to capture one s attention.

Since geodes have hollow spaces in the middle they will weigh less than other rocks of the same size. Geodes derived from the greek word γεώδης meaning earth like are geological secondary formations within sedimentary and volcanic rocks geodes are hollow vaguely spherical rocks in which masses of mineral matter which may include crystals are secluded. Geodes are like the tootsie roll pop of the geology world because underneath the hard exterior lies a surprise center. So compare the weight of the rock you think might be a geode with another one of the same size.

What you want to do is check the weight. The only difference between a geode and a nodule is that a geode has a hollow cavity and a nodule is solid.