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Maryland, a state known for its diverse scenery and blue crabs, has a wide variety of collectible rocks and minerals. With unique rocks, such as the Patuxent River Stone, and popular minerals, such as beryl, Maryland is a great state for any rockhound to visit.
The Old Line State has an interesting array of rocks and minerals, including:
- Patuxent River Stone,
- soapstone,
- puddingstone,
- geodes,
- sea glass,
- agate,
- marble,
- fossils,
- beryl,
- serpentine,
- tourmaline,
- mica,
- and garnet.
Whether it’s your first time rockhounding in Maryland or if you are a seasoned expert, information is always helpful. Navigate Maryland’s geology and rockhounding environment with this informative guide.
If you are interested in checking out the best rockhounding tools you can find them by clicking here (Amazon link).
What Rocks Are Found in Maryland
If you want to collect some rare and unique stones, Maryland has plenty of rocks to offer, including:
Patuxent River Stone
| Location | GPS Coordinates |
|---|---|
| Patuxent River | 38.395953, -76.548870 |
| Calvert County | 38.353494, -76.474338 |
| Dunkirk | 38.723484, -76.690099 |
| St Mary’s County | 38.478732, -76.667424 |
| Hollywood | 38.359338, -76.513592 |
| Prince George’s County | 38.694024, -76.711847 |
The Patuxent River Stone, also called the River Stone Agate, is Maryland’s state gemstone. Although these stones are called agates, River Stone Agates are technically not agates since they are composed of colored quartzite.
These stones appear in red, orange, and yellow hues, and they are often discovered on the shores of the Patuxent River.
As you might expect, the Patuxent River Stone is often found along the Patuxent River, which winds through many of Maryland’s counties. Other rivers and waterways nearby are also fair game for this stone.
TIP: River rocks are actually any kind of rock that’s been tumbled and polished by the rushing water in a river. Find out more about river rocks in the article below:
River Rocks: This Makes Them Smooth and Round (How & Where)
Soapstone
| Location | GPS Coordinates |
|---|---|
| Rock Springs | 39.715849, -76.157941 |
| Cecil County | 39.716476, -76.140389 |
| Funks Pond Recreational Area | 39.672458, -76.168730 |
| Coopstown | 39.591828, -76.427746 |
| Reed Mine | 39.614737, -76.461930 |
| Walkens Mine | 39.611889, -76.457203 |
Maryland has a wide variety of soapstones, ranging from light or dark gray to green in color. Many of the soapstones found in Maryland also have unique patterns running through the rock, making them beautiful stones for carving or collecting.
Rock Springs, Cecil County, and Funks Pond Recreational Area are some of the most popular places for finding soapstone in Maryland. The Reed Mine and Walkens Mine near Coopstown also have plenty of soapstone for rockhounds.
Puddingstone
| Location | GPS Coordinates |
|---|---|
| Point of Rocks | 39.272770, -77.536693 |
| Frederick County | 39.483475, -77.455171 |
| Montgomery County | 39.203077, -77.319388 |
| Prince George’s County | 38.694024, -76.711847 |
| Potomac | 39.023387, -77.201105 |
| Bull Run Formation | 39.512739, -77.757168 |
Quartz conglomerate has many names, but its most famous name is puddingstone, and it’s a great find for any rockhound in Maryland.
This eye-catching sedimentary rock has a unique and colorful pattern that looks similar to chopped fruit in a pudding, hence the name. Puddingstone is a rare rock, but fortunately, there are multiple places to find it in Maryland.
The areas and counties near the Virginia/Maryland border are known for their puddingstone. Check out the Point of Rocks, Potomac, and Frederick County for this multicolored rock.
Geodes
| Location | GPS Coordinates |
|---|---|
| Rock Springs | 39.716360, -76.157233 |
| Cecil County | 39.716476, -76.140389 |
| Hartford County | 39.459777, -76.216149 |
| Baltimore County | 39.499985, -76.634273 |
| Carroll County | 39.595570, -76.982096 |
| Frederick County | 39.437883, -77.365907 |
No matter where you travel in the Old Line State, you’ll be able to find geodes. Geodes filled with quartz, mica, and feldspar are common in Maryland, but they are scattered throughout the state. Your best bet for finding geodes in this state is to visit a location that’s known to have geodes.
If you want to collect geodes from Maryland, visit Hartford County, Baltimore County, and Cecil County. Rock Springs is also a popular destination for geode hunters.
Sea Glass
| Location | GPS Coordinates |
|---|---|
| Chesapeake Bay | 38.694999, -76.487465 |
| Tolchester Beach | 39.221320, -76.240703 |
| Kent County Beaches | 39.251435, -76.224567 |
| North Beach | 38.709261, -76.530135 |
| Oxford Beach | 38.689770, -76.174148 |
| Sandy Point State Park | 39.019194, -76.404100 |
Planning a trip to Chesapeake Bay? If so, get ready to collect some beautiful and rare pieces of sea glass from the beaches!
Chesapeake Bay is famous for its sea glass, and rockhounds flock to its beaches to collect these attractive stones. You can find all sorts of rare colors of sea glass along the shores of Chesapeake Bay, such as cobalt blue or bright orange.
Some of the best Maryland beaches to visit for sea glass include North Beach, Tolchester Beach, and Oxford Beach.
TIP: By making your own sea glass, you can have much more significant quantities to craft with or use in the garden. Check out the complete guide in the article below:
Step-by-Step: Making Sea Glass With & Without Rock Tumbler
Agate
| Location | GPS Coordinates |
|---|---|
| Bare Hills | 39.387028, -76.652797 |
| Flintville | 39.704787, -76.248380 |
| Hartford County | 39.414170, -76.221633 |
| Baltimore County | 39.604813, -76.708421 |
| Delight | 38.654316, -76.896651 |
| Catonsville | 39.261521, -76.729464 |
There are many types of agates that rockhounds can find in Maryland, including banded and moss agates. Some rockhounds consider the Patuxent River Stone to be an agate, but others do not, so there is an ongoing debate in the rockhounding community on this subject.
Since we have a section on Patuxent River Stones above, this section focuses on banded, moss, and other agates. Although Maryland isn’t as well-known for its agates as other U.S. states, you can still find these colorful and unique rocks in the Old Line State.
Although the popular opinion among rockhounds is that Maryland doesn’t have many agates, you can find agates in this state as long as you know where to look! Explore Flintville, Catonsville, and Bare Hills for banded and moss agates in this state.
Marble
| Location | GPS Coordinates |
|---|---|
| Baltimore County | 39.342978, -76.772966 |
| Clarksville | 39.201538, -76.950476 |
| Union Bridge | 39.554133, -77.172749 |
| Frederick County | 39.566611, -77.232651 |
| Hartford County | 39.526542, -76.276564 |
| Howard County | 39.232931, -76.954835 |
| Cockeysville | 39.477937, -76.629682 |
Did you know that the marble used for the Washington Monument was from Maryland? The Old Line State has some of the highest-quality marble in the U.S., and it’s called Cockeysville Marble.
This white marble is not only beautiful, but also extremely durable. In addition to white marble, rockhounds also collect pink and green marble from specific areas.
For pink and green marble, stop by the areas near Union Bridge. For Cockeysville Marble, Baltimore County is the best place to search.
Fossils
| Location | GPS Coordinates |
|---|---|
| Calvert Cliffs State Park (surrounding areas) | 38.406916, -76.412054 |
| Chesapeake Bay | 38.447409, -76.454595 |
| North Ferry Point | 39.083824, -76.501483 |
| Hancock | 39.698900, -78.172333 |
| Lusby | 38.356913, -76.437639 |
| Howard County | 39.232931, -76.954835 |
If you are the type of rockhound who enjoys collecting fossils, Maryland has much in store for you. Oyster shells, shark teeth, and even dinosaur fossils can be collected from Maryland, and you can find these in the central counties of the state.
There are over 600 species of fossils from the Miocene era alone in Calvert Cliffs State Park, so there is no telling what you might discover during your trip!
Without a doubt, Calvert Cliffs State Park is one of the best places to look for fossils in Maryland. Keep in mind that visitors are not allowed to dig near the cliffs but can do so in surrounding areas.
Recommendation box: All tools and equipment you need for rockhounding and rock identification* (Amazon links):
1. Estwing Rock Hammer – Light, comfortable, and extremely durable hammer.
2. Estwing Geologist Pick – Classic and the most trusted paleo pick in the world.
3. Finder 12-inch Chisels – Heavy-duty chisels set with hand protection.
4. Mini Handle Shovel – This is a great tool for digging deep in the dirt.
5 Ironclad Utility Work Gloves – Breathable, but they also protect the areas requiring them most.
6. 3M Safety Glasses – Comfortable and efficient goggles for rockhounding.
7. Convoy 8+ UV Light – 365nm UV LED flashlight with a patented glass filter.
8. Wesley’s Jewelers Loupe – High magnification options (30X and 60X) with carrying case.
9. Mohs Hardness Kit – A specially designed kit for rockhounds
*All recommended products are personally tested and regularly used by experts from this website.
What Minerals Are Found in Maryland
You can find all kinds of gems and minerals in Maryland, such as:
Beryl
| Location | GPS Coordinates |
|---|---|
| Baltimore County | 39.342978, -76.772966 |
| Elk Mills (surrounding areas) | 39.653490, -75.821316 |
| Kensington Mica Mine (surrounding areas) | 39.056568, -77.011990 |
| Scaggsville | 39.145616, -76.899710 |
| Howard County | 39.232931, -76.954835 |
| Daniels | 39.316506, -76.816836 |
Beryl and its variants are known for their stunning shine and vivid colors, and you can find these valuable gems in various areas of Maryland. The most common types of beryl in this state are emerald and aquamarine, two very valuable gems that are highly prized among rockhounds.
Baltimore County and Howard County are both excellent places to search for beryl, specifically emeralds and aquamarines.
Serpentine
| Location | GPS Coordinates |
|---|---|
| Cecil County | 39.626287, -75.923725 |
| Bare Hills | 39.387028, -76.652797 |
| Chrome Hill | 39.626968, -76.409499 |
| Low’s Mine (surrounding areas) | 39.721081, -76.183626 |
| Soldier’s Delight | 39.413643, -76.843997 |
| Reed Mine (surrounding areas) | 39.614737, -76.461930 |
| Ashton | 39.629632, -77.915684 |
Maryland is a great place to be if you want to find gem-grade serpentine. This light green mineral is all over the place in this part of the U.S., and there are a couple different types that rockhounds can find.
The first type of serpentine is known as willemite, which is a transparent form of serpentine that’s a rich, dark green. This stone is highly valuable because of its green hues, but due to its fragile nature, it’s not typically used for jewelry.
Another form of serpentine that exists in the Old Line State is bowenite, which looks similar to jade. This mineral has been classified as a semi-precious stone, and it can be used for jewelry or tools due to its durability.
Bring home some gem-quality serpentine after you visit Cecil County, Bare Hills, or Chrome Hill. You can also comb through the areas outside of the nearby mines, including Low’s Mine and Reed Mine.
Tourmaline
| Location | GPS Coordinates |
|---|---|
| Baltimore County | 39.342978, -76.772966 |
| Chrome Hill | 39.626968, -76.409499 |
| Montgomery County | 39.142209, -77.265096 |
| Rockville | 39.084395, -77.160397 |
| Granite | 39.342484, -76.855961 |
| Castleton | 39.674365, -76.213218 |
Inside Maryland’s granite pegmatites, rockhounds often uncover tourmaline. Maryland tourmaline can come in multiple different colors, and it’s high-quality. One type of tourmaline that’s produced in this state is chrome tourmaline.
This type of tourmaline forms near chromium mines, and it’s known for its lovely green color; some specimens are almost indistinguishable from emerald!
The pegmatites and mines in Baltimore County, Chrome Hill, and Montogomery County have more than enough of this mineral for rockhounds.
TIP: To better understand how to find tourmaline in nature, it’s essential to know how this mineral usually forms. Find out more in the article below:
Where to Find Tourmaline: Best Environments & Locations (USA)
Mica
| Location | GPS Coordinates |
|---|---|
| Montgomery County | 39.142209, -77.265096 |
| Baltimore County | 39.342978, -76.772966 |
| Bald Frier | 39.704868, -76.213376 |
| Flintville | 39.704787, -76.248380 |
| Kensington Mica Mine (surrounding areas) | 39.056568, -77.011990 |
| Elk Mills | 39.653490, -75.821316 |
Mica is abundant in Maryland, and the mines for this mineral are spread throughout various areas. While white and green are the most common colors, rockhounds can also come across black mica in the Old Line State.
The color of mica you find will depend on the location you visit. For example, if you want to find mica with a silvery appearance, central Maryland is the place to go.
Montgomery County, Baltimore County, and Bald Frier are a few places that are known for their mica. And even though you might not be able to visit the mica mines themselves, you can visit the surrounding areas for this mineral.
Garnet
| Location | GPS Coordinates |
|---|---|
| Baltimore County | 39.342978, -76.772966 |
| Montgomery County | 39.142209, -77.265096 |
| Cardiff | 39.717062, -76.337737 |
| Bare Hills | 39.387028, -76.652797 |
| Granite | 39.342484, -76.855961 |
| Chrome Hill | 39.626968, -76.409499 |
| Hunting Hill | 39.082472, -77.220434 |
Grossular garnet is the main type of garnet that’s found in Maryland, and it ranges from yellow to red to green in color. This type of garnet has one of the widest color ranges for garnet, and in the Old Line State, they can appear in clusters or single crystals.
Swing by Hunting Hill, Chrome Hill, or Bare Hills to add some Maryland garnets to your rockhounding collection.
TIP: While Maryland may not be the first place that comes to mind when you hear the term ‘gold prospecting,’ it might surprises you. Find out more in the article below:
Gold Prospecting in Maryland: 7 Best Locations & Laws
FAQ About Common Rocks & Minerals in Maryland
Dive deeper into Maryland’s geology and rockhounding opportunities with these FAQs:
What Rare Rocks Can You Find in Maryland
Any rockhound who visits Maryland and wants to add rare rocks to their collection is in for a treat! There are all kinds of beautiful and rare rocks that exist in Maryland, such as Patuxent River Stones, agates, jaspers, puddingstone, Cockeysville Marble, geodes, and sea glass.
A popular stone that rockhounds often find in the Old Line State is amber. Although amber is not a mineral or a rock since it’s from a living organism, it’s still a great addition to a collection, and there’s plenty of high-quality pieces in Maryland.
Baltimore County, Montgomery County, and Chesapeake Bay are some of the best rockhounding sites in Maryland. You can find multiple rare rocks in each of these areas, and you can even find valuable minerals, as we will discuss in the section below.
What Rare Minerals Can You Find in Maryland
The first rare mineral that pops into most rockhounds’ heads for Maryland is serpentine, namely willemite.
And even though Maryland has gorgeous, gem-quality serpentine, there are other rare minerals that exist in the state. Some other rare minerals include emeralds, aquamarines, garnets, tourmalines, amethysts, zoisite, and fluorite.
Baltimore County, Bare Hills, and areas near Kensington Mica Mine are all known for their wealth of valuable and rare minerals. Rockhounds also frequent Chrome Hills, Mongomery County, and Elk Mills for rare minerals and gems.
BTW: Do you want to know more about rock and mineral identification? The books listed below are the best ones you can find on the internet (Amazon links):
- Smithsonian Handbooks: Rocks & Minerals
- Gemstone & Crystal Properties (Quick Study Home)
- Ultimate Explorer Field Guide: Rocks and Minerals (National Geographic Kids)
What is the Most Famous Rock or Mineral Found in Maryland
Since Maryland is the only place in the world where you can find Patuxent River Stone, it makes sense that it’s the most famous and most popular rock in the Old Line State.
Patuxent River Stones are known for their unique red, orange, and yellow hues, and they are sometimes referred to as River Stone Agates despite the fact that they aren’t composed of agate.
These colorful rocks are composed of quartzite, and even though quartzite isn’t very intriguing for some rockhounds, these specific stones are not found anywhere else in the world, so they are special and unique.
To find Patuxent River Stones in Maryland, start at the areas near the Patuxent River. This large river runs through many counties in Maryland, so there are plenty of areas to explore.
Conclusion
Who would have guessed that Maryland, a state that’s famous for its blue crabs and the city of Baltimore, would have so many unique rocks and minerals!
Due to its valuable, gem-quality serpentine, Patuxent River Stones, world-class marble, and valuable beryls, Maryland is a must-see destination for rockhounds.
Whether you visit Maryland specifically for rockhounding or if you just want to pick up a couple of keepsakes along the way, you’ll find that this unassuming state has much more than you expected!
TIP: Maryland may not appear to be an exciting rockhounding state at first appearance, but there are a few sites worth visiting. Check out the complete guide in the article below:
GUIDE: Best Rockhounding in Maryland & What Rocks to Find