Common Igneous Rocks Found In Tennessee (A Rock Hunter's Guide)

For some, rock hunting is in the bones.

With so many unique and amazing minerals out there, how can some rock hunters resist?

In this guide, we’ll be looking at three kinds of igneous rocks found in the state of Tennessee, some facts about each one, and where to possibly find them.

Common Igneous Rocks Found In Tennessee (A Guide)

Geodes

One such rock commonly found among igneous rocks is the geode.

They are defined as being spherical, somewhat hollow, and a treasure trove of mineral matter on the inside.

Within basaltic lava, pockets of gas can occur, and the end-products can become geodes.

After the lava cools off, these pockets accumulate dissolved carbonates and/or silicates on the inside, giving them their wonderful appearance once cut open.

Some can contain amethysts, fluorite, and even ancient fossils!

Geodes are nature’s surprise gifts, as you can never be sure what beauty you’ll find on the inside.

They are valued for their inner beauty and primarily used for display pieces.

Geodes can be small, or very large in size.

There is some debate over which geode in the world is the largest, with the two contenders being the Crystal Cave in Ohio, or the Pulpi Geode in Spain.

The one in Ohio is lined with 3-foot long celestite crystals, and the whole thing measures up to 30 feet!

One source depicts the geode having been larger when it was first discovered in 1887 by a German immigrant, Gustav Heineman.

To this day, it serves as a tourist attraction near the village of Put-in-Bay.

The other geode, which can be found near the Spanish town of Pulpi near an abandoned silver mine, contains 6-foot translucent selenite crystals, with the entire geode measuring a staggering 26 feet long and 5.5 feet high!

To find these treasures in the state of Tennessee, there are several locations you can try. For example, one such place lies in Cannon County, Rainbow Falls Park, just south of the town of Woodbury.

You can get there by driving on the 70S highway heading south.

The ideal sight is within a forested area, so you may have to do some serious digging before finding your prize.

Before you head out with your rock pick and field shovel, first call the necessary authorities to ensure that any geodes you mine for and collect are under legal circumstances.

In the state of Tennessee, there’s a high possibility that you’ll need to apply for a “Surface Mining Permit,” a form which regulates any mining activity on state public land.

This may not be the case for every mineral out there, but it would be a very good idea to contact the Tennessee Division of Water Resources, Mining Section, just in case.

The application fee is an annual $250, with more fees included depending on how much mining you do.

There’s also the chance that any place you find geodes could stretch onto private property.

To search for and collect any minerals would require acquiring permission from the land owners.

Always keep the legalities in mind when hunting for rocks.

Some other locations where you can find geodes are around quarries slightly north of the community of Allons; or even forested areas slightly east of the community of Russellville.

Quartz

Another igneous mineral to look out for is quartz.

It’s a crystalline rock made of silicon dioxide (SiO2).

The name “quartz” comes from the 14^th century Polish word “kwardy,” which essentially means “hard.”

Quartz can come in many colors, such as red, purple, yellow, blue, and so much more.

Lots of quartz come in a clear variety, so look out for minerals that appear translucent to transparent.

To find your own quartz, try searching for a place called Gulf Fork Big Creek, an area 3 miles north of east from the community of Hartford.

Remember to contact the Tennessee Division of Water Resources, Mining Section before you head out.

Another location you can try lies approximately 2 miles northwest from the city of Copperhill, and around 560 feet from the Ocoee River.

Aside from being used as gemstones, quartz is primarily used in the electronics industry in the form of piezoelectrics.

By applying physical stress, the quartz crystal accumulates an electric potential.

Many of these crystals are used in watches and other clock products to help maintain accurate time-keeping.

Kimberlite

Our third igneous rock you can find in Tennessee is kimberlite.

The mineral tends to be dark in color, depending on the magma composition that formed it in the first place.

It got its name from the South African town Kimberley, where a massive 83.5-carat diamond called the “Star of South Africa” was found in 1869.

Ever since, kimberlite has been associated as the main mineral that contains diamonds.

It can occur vertically as kimberlite “pipes,” igneous dykes, or even horizontal “sills.”

Such formations are the result of magma being brought closer to the surface, and can sometimes carry valuable gemstones along with them.

Not only have they been the primary source of diamonds, but they can also carry other valuable minerals such as garnet stones and magnetite.

It can be difficult to determine where the kimberlite will be exactly, so make sure you have permission from either the private land owner or the Tennessee Division of Water Resources, Mining Section, before you begin hunting for that igneous kimberlite rock.

One such place that has kimberlite is Norris Lake in Union County, just north of the city of Knoxville. In 1869, two diamonds were found several miles downstream from the lake’s kimberlite pipes.

The kimberlite itself, however, has been noted to be exposed along the lake shoreline, so finding some kimberlite of your own should not be that difficult.

You might also like: Is Kimberlite Magnetic?

So remember, before you begin your exciting rock-hunting expedition, contact the necessary authorities, talk to any private land owners you may encounter, ensure you have the right equipment such as a field shovel and steel rock pick, ask for directions from the locals if you’re having trouble getting to the site, know what you’re looking for, and most importantly, enjoy the adventure!