Types of Rocks Found In Colorado: A Guide To The Most Common You’ll Spot

The state of Colorado is full of mountainous wonders and breath-taking outdoor sights.

On your adventure, you might come across a rock that you’ve never seen before.

Just what the heck is it?

In this article, we’ll look at the characteristics of six rocks that you might stumble upon in this beautiful state.

Types of Rocks Found In Colorado: A Guide

Rock #1: Zircon

Also known as zirconium silicate (ZrSiO4), Zircon belongs to the nesosilicates mineral group.

Zircon crystals are tetragonal in shape, meaning they will appear as rectangular prisms.

Their color ranges from yellow-golden, brown, red, blue, colorless, and green.

The name “zircon” originates from the Persian word “zargun,” which means “gold-hued.”

Zircon has ancient origins in human history.

The earliest mention of zircon was one of twelve gems worn by Israeli high priests in the bible.

Much later on, in 1789, it was named “Zirkonerde” by Martin Heinrich Klaproth, a German chemist.

Afterwards, in the early 1800’s, an English chemist by the name Sir Humphry Davy re-named the stone to “Zirconium.”

Today, it’s still used as a semi-precious gemstone, but also as an additive to make substances more opaque, and in radiometric dating to determine the ages of certain rocks.

This stone can occur in all kinds of rocks, such as metamorphic, sedimentary, and igneous, but finding a crystal larger than 0.0118 inches is quite rare.

One place you may find a sample lies in the mountains west of Bear Creek Regional Park, Colorado Springs.

From a place known as Bear Canyon, you’d have to hike a total of 1,760 feet westward to a spot known to have zircon minerals.

However, keep in mind that any mining that disrupts the natural landscape is strictly prohibited on Colorado public lands.

You may get lucky and are simply able to chip off a zircon crystal from a rock face, but do not dig deep into the ground for these gemstones.   

Also, be aware of any dangerous wildlife that might be roaming out in these desolate areas.

Some animals to watch out for are Mountain Lions, Bull Elk, Bull Moose, Mountain Goats, and Colorado Bighorns.

Rock #2: Amethyst

This stone will appear as a translucent to transparent crystal.

It’s a variety of quartz, meaning it has a silicon dioxide (SiO2) chemical composition.

Amethyst crystals tend to have a trigonal shape.

This mineral was used as far back as the ancient Greeks in the form of wine goblets.

They believed it could prevent people from getting drunk, hence their word “amethystos,” which translates to “not intoxicate.”

Once the 18th century arrived, and lots of deposits were found in Brazil, Amethyst was demoted to a semi-precious gemstone, whereas before it had the same relative value as rubies and even diamonds.

Amethyst today has the same use in the form of gemstones and collectable items.

They can commonly form inside geodes, which can be taller than your average human being!

The rarest and most valuable type of amethyst is referred to as “Deep Russian,” a very dark purple variant of the mineral.

To find a sample of your own, try visiting a site on West Willow Creek, a river that runs on the west side of Campbell Mountain.

The site noted to have amethyst samples is approximately 1.05 miles southeast of the Last Chance Mine, which is privately owned.

In the case of private land, always make sure you get the owner’s permission before traveling and collecting rock samples.

Their website does not mention what fees need to be paid, but you can try contacting them.

Also, remember that when in the mountains, dangerous wildlife can be nearby.

Rock #3: Agate

The third rock that you may find is agate, a mineral composed of quartz (SiO2) and chalcedony.

It’s well-known for its many colorful bands, which can be cut into very pristine display pieces.

The first recorded instance of agate being found was by Theophrastus, a naturalist and Greek philosopher around the 4th and 3rd centuries BCE.

It was discovered along the Dirillo River shoreline, near modern-day Sicily.

Today, agate is used to make mortars and pestles and other kinds of precision lab equipment due to its relative hardness of 6.5-7 on the Mohs scale.

Agates typically form as nodules within the cavities of volcanic rocks.

These cavities are then filled with fluids rich in silica and slowly make their way inwards, forming bands of different mineral compositions and colors.

A location that is known to have agates is Specimen Mountain, which lies north of highway 34.

However, some parts of this highway are closed during winter.

You will also have to hike up to the rocky mountain side if you want a chance at finding an agate.

It’s also on public land, so you won’t be able to dig too deep for it.

Rock #4: Garnet

Garnet comes in the form of shiny dark red stones that can have either a cubic or rhombic dodecahedron shape.

Common compounds found in most garnets are silicate minerals, and are of the nesosilicate mineral family.

The name “garnet” came from the 14th century English word “gernet,” which translates to dark red.

In ancient times, garnet was used for abrasives and gemstones.

Today, the mineral is used for many of the same purposes.

Garnet is commonly used as a substitute for silica sand when sand blasting.

Such a method is capable of cutting through steel.

It’s also referred to as the birthstone for those born in January.

Like most stones on this list, finding a garnet stone will take a lot of hiking in the wild areas of the state.

One such site is about 3,400 feet north of “Home of Ingrid Burke and William Lauenroth,” and 915 feet eastward away from an intersection of 27 road and Fire Rte 15.

This area is fairly remote, so be wary of the weather and any wild animals you might encounter.

Rock #5: Pyrite

Commonly known as “fools gold,” this mineral is still a nice treat to find during a hiking trip.

It’s an iron sulfide with FeS2 (iron (II) disulfide) as its chemical compound.

This metallic and brass-yellow colored rock is the most common sulfide mineral, and commonly comes in cubic shapes.

The name “pyrite” derives from the Greek words “pyrites lithos,” which roughly translates to “stone or mineral which strikes fire,” due to its ability to create sparks when struck against a hard surface.

In history, around the 16th and 17th centuries, pyrite was a popular source of ignition in some early firearms, with the wheellock being a prime example.

Using a circular file, pyrite could produce sparks to fire a gun.

Today, Pyrite has multiple uses; from being used as a semiconductor material, a main component in the production of sulfur dioxide, a mineral detector in radio receivers, used to make marcasite jewelry, and has been proposed for use in low-cost photovoltaic solar panels.

Most pyrite can be found alongside quartz veins, metamorphic rock faces, sedimentary rock, and coal beds.

A site known to have pyrite in Colorado is quite far away from any settlement, approximately 4.53 miles east of Buckhorn camp.

There is, however, a small path from which you can drive, known as clear ridge road.

Once the road ends, you’ll have to hike about 2,500 feet north.

Rock #6: Copper

The final rock on our list sports a red-orange metallic luster, is very malleable, and comes with high electrical and thermal conductivity.

However, in the wild it will appear more green or blue due to the mineral being mixed with other compounds such as malachite, azurite, and turquoise.

Copper has been used by humans since 8000 BC.

Being one of the easiest metals to mold and shape, copper was used for a huge number of materials, from all kinds of tools to jewelry.

In modern times, copper makes up a majority of all electric wire, various parts in industrial machinery, used in plumbing and roofing, and even mixed with other alloys to create bronze and brass.

It’s also extensively used in electronics, architecture, antimicrobial applications, and renewable energy production.

Seeing as it’s the 25th most abundant mineral on earth, it can be found just about anywhere.

However, stumbling upon copper on a hiking trip can be a bit difficult, due to how deep copper deposits are known to be.

A place you can try finding some for yourself lies about 3 miles east of Tolvar Peak, and a 1,870 feet hike east of highway 149.

Whether this area is public or private is uncertain, and you’ll have to check with the state to see what kind of land it is before heading out.

However, if you happen to come across some bright green rocks on your hiking adventures, you might’ve just stumbled across some copper.

In either case, watch out for animals!

With its extensive mountain terrain, Colorado is a truly marvelous place to visit and explore.

Now that you have some extra knowledge, you might just come across a shiny new rock as a souvenir.

Types of Rocks Found In Colorado: