How to Cut a Geode

By Trish Popovitch
A split open geode rock.

A geode is a beauty of the natural world, consisting of a round rock that contains crystallized minerals on the inside. Before opening a geode, it is impossible to know exactly what if anything is on the inside. Usually, geodes are very round and lighter than normal rocks of a similar size. There are several methods and tools used for cutting open geodes.



Process

Placing the geode into a vise and using a diamond saw is one way to split it into two.

Place the geode rock in a carpenter’s vise and use a diamond saw to cut in half by sawing down the center. This is the most expensive yet easiest way to cut a geode. A diamond saw is a piece of expensive specialist equipment and the purchase of such should be reserved for the geode enthusiast who intends to cut hundreds of geodes rather than just one or two.

Correcty using the right settings on a iron pipe cutter will split the geode in two.

Wrap the chain of an iron pipe cutter around the geode and attach on the correct notch on the tool before pushing down on the handle. This should cut the geode exactly in two although, like the diamond saw, is an expensive piece of equipment and not worth the money if the intention is only to cut one rock in half.

A metal hammer and chisel will punture into a geode.

Push a chisel point into the geode at four different points along the middle to mark out a circumference line. Tap the chisel gently with a metal claw hammer to punctuate the surface.

Score the surface of the geode with the chisel.

Use a stone chisel to lightly score the entire circumference of the geode. Use the sharp end of the chisel and just the strength of your own arm to make a small chip to create a dent around the entire stone. Chip so that the geode is separated by a line into two roughly equal parts.

Use a hammer to assist the chisel as you break through.

Repeat the chipping process but this time using the gentle assistance of a hammer. Be sure to tap gently on the blunt end of the chisel as you continue to work your way around the circumference of the stone. Place the rock on the ground outside to provide a hard surface for reverberation.

The rock will eventually break into two revealing the crystals.

Continue to work around the rock until a crack develops. Follow the crack around with gentle tapping on the chisel until the rock breaks in two.

Tip

Be sure to wear safety goggles and shard-proof gloves when breaking stone.

Warning

Avoid simple hitting the geode heavily with a hammer as this will shatter the stone and destroy any crystallization on the interior.

About the Author

Trish Popovitch is a freelance writer with 10 years of professional writing experience and a degree in the social sciences. A former print journalist and current blogger and magazine writer, her content writing is a reflection of her varied background.