One thing I have enjoyed is obtaining and learning about the different geological hammers and tools used for finding and extracting fossils. I started with the Estwing bricklayer’s hammer. It features a flat chisel back, which is very useful for splitting shale. Below I’ll review and discuss several different hammers and tools I’ve used over the past couple of years.
In fossil collecting, you first need to get the rocks out of the ground. Rock picks are great tools for these, slicing into the ground and forcing rocks to move. There are two primary rock types I deal with, limestone and shale.
Limestone vs Shale and the tools to work them
Limestone is a natural cement, and locally this means a silty/sandy mix fused together with calcite. There are planes throughout the rock that can be split using a direct hammer blow or by using a chisel and a hammer together. However, these are not always flat and often curve and snake through the specimen. Embedded fossils can also create cleavage planes. This makes separating limestone a chore, but the different types of hammers can help.
The shale is fine sediment that is loosely held together and is very fissile. This means easily split along natural planes in the rock. A hammer with a flat chisel back can be used to split one rock into several flat pieces for inspection. There are certainly particular planes within the rock that are easy to separate, and others can be more or less hard to split.
The 508 million-year-old Burgess shale, a famous Cambrian deposit in Western Canada, is explored by carefully splitting the shale using special flat pieces of metal and exposing beautiful preserved soft creatures from half a billion years ago.
In Parks township, we have plants and other creatures in the shale. There are layers that contain mostly plant fossils, and the layers closer to the limestone can contain crinoids, brachiopods, clams, cephalopods, and all sorts of unique fossils. However, being preserved in shale can often mean the resulting specimen is much more fragile. The specimens themselves are also often fissile.
So, these are the tools to use for extraction. After going through all the different hammers and extraction tools, I’ll discuss other tools I’ve bought just for fossil hunting.
All of these tools should be used with the proper eye-wear. Aside from the potential of flying steel fragments, rock always finds a way to your face. Even the smallest tap can bring rock particles to your eyes. Always shield your face properly and be aware of your surroundings. Especially if people are near. I’ve had people within 15 feet of me that get struck with rock fragments when these tools meet the matrix. Clear the area of anyone and anything you care about. Also, never use a hammer to drive another hammer into a rock. That is what cold-forged chisels are for. Have fun, but be safe doing it!
Geological hammers & tools
Below you will find personal reviews of real-world amateur use of these tools to collect fossils. I have been using these for 18 months at this point. When I first started, I searched the internet for how to use these and came up empty. I have figured out what’s best through experience with each tool.
Estwing Rock Pick – 22 oz. – E3-22P
If I were to pick one hammer to use for finding fossils, this is it. This was the second hammer I purchased. I wanted the pick end, which is useful for digging between rocks and tearing up the terrain. The square hammer portion strikes well and is useful for cracking the hard limestone locally. There are three primary grips you can get. The leather grip is by far the best looking, but is natural and will wear out quickly. The blue rubber grip is modern and probably the best overall grip. There is also a bright orange variation.
Use the pick end for prying between layers of rock. I have used this end to lightly strike but this should be done with caution and eye-wear. It is strictly forbidden to do so by the manufacturer as it highly increases the likelihood of metal flying. I use it to try and separate pieces along natural faults in the rock. It is very sharp but wears down quickly. It can be sharpened as needed. I have never resharpened mine.
There are other variations of this rock hammer. One has a longer handle, and there is a special edition paleontology version with a leather grip and black painted metal. There is a logo with a Tyrannosaurus skull imprinted into the leather. While it’s very cool looking, it’s also double or more the price of the standard rubber blue grip version. And the blank paint will wear off with use.
Estwing Rock Pick – 13 oz. – E13P
This is the smaller version of the 22 oz. pick. It’s very useful for light work, but you’ll quickly miss the striking power that the 22 oz. provides. However, you’ll curse the weight of the heavier one when carrying it, so the 13 oz. has its use. Unless you are working with softer work, I would make sure the heavier version is nearby to break tougher rock if needed. I purchased the version with the leather grip, mostly for looks. The grip has worn down pretty fast with lots of use. There is a clear coating to protect it, and general use in the mud and rocks has worn it away.
I would recommend this hammer as one to have in the car with you. It is useful if you stop somewhere unplanned and need a rock pick. While I wish the black lines in the handle were a useful measurement, they are actually 4 5/8″ center to center, not so useful in the field. Geologists will often mark handles with tape at a standard distance, such as 6 inches to use in the scale of photos of geological terrain.
Estwing E3-22P 22 oz. and E13P 13 oz. side by side comparison
The hammers have nearly the same length. The handle is shorter on the 13 oz. version. The pick also comes down to a point at a hard angle on the 13 oz. compared to the rounded appearance of the 22 oz. The 13oz has a long flat bar past the handle. I’ve seen reports of bent handles on some 13 oz., but I would imagine that is rare and can easily be returned and replaced.
The 22 oz. is much better at breaking apart a much greater range of rocks. The 13 oz. will have a bounce-back action when you hit a rock too big, where the blow won’t bury itself into the rock. You’ll come to appreciate the smaller hammer when you are cleaving off bits of the matrix from a field specimen.
Estwing Gad Pry Bar – 18″ Forged Geological Tool with Pointed Tip & Chisel End – GP-18
I’ve only used this geological tool a couple of times, but it gets great reviews online. The chisel end is no joke, coming to a wide sharp point. It’s highly useful for moving huge rocks with very little force using the lever end. The main handle part of the tool has an i-beam shape to provide a great deal of strength when prying. As you can see in the detailed photos of the ends, the point actually expands out past the width of the i-beam.
Estwing Geo/Paleo Rock Pick – 25″ GP-100
Part of Estwing’s Big Blue line, this pick is excellent for removing large amounts of ground quickly. When pulling limestone boulders from the hillsides, it quickly helps to eliminate the loose rock around the boulder. It feels smaller in person than it looked online. The 25-inch length is true. A few strikes on solid rock with the wedge end dinged it up a bit.
The grip is made for comfort, being made of a spongy rubber. The handle is circular. The pick end is really good for burying into shale and prying it out of rock outcrops.
The blade and pick end on the Estwing GP-100.
Estwing Burpee Rock Pick – 17″ BP500
This is somewhat of a smaller version of the GP-100. It was specially made by Estwing after input from rock-hounds and geologists. One end is a chisel point, the other resembles a very large nail. The entire hammer seems like it is made from a single piece of steel, but it’s likely solid welded steel components. Great for picking through and loosening tightly packed shale. There are magnets embedded in the head to use for testing if found minerals are magnetic.
Three embedded magnets for testing found materials / minerals.
Estwing Bricklayers/Mason’s Hammer – 22oz – E6-22BLC
This is the first hammer I purchased. I wanted a hammer just for working rocks and this was all Lowe’s had at the time. You’ll find that rock hammers in general are rare at hardware stores. The chisel tip is great for splitting softer rocks, but not something I would use for limestone. Not being a true pick, it makes it difficult to use for pulling rocks out of the hillside.
Estwing Drilling/Crack Hammer – 3-Pound Sledge – B3-3LB
The mini sledge, it’s a solid piece of steel. Unlike typical sledgehammers, the head cannot separate from the handle unless the forged steel snaps. This was my go-to hammer for cracking apart limestone until I obtained the Fiskars Pro IsoCore 4lb Club Hammer (see below). The B3-3LB has two flat striking heads which are great for general blows and force. However, the Fiskars hammer offers a wedge-style head which is more useful for splitting rock.
Fiskars IsoCore 4 Pound Club Hammer – 750810-1001
This hammer is an upgrade from the B3-3LB for two reasons. One, it’s just a pound heavier, so you get more weight per strike. The head features a wedge side, which allows for splitting of large boulders which I typically do. The handle is a composite of steel and plastics, which allows for shock absorption, but I do hope it never breaks. Fiskars has an excellent lifetime guarantee. I have a solid steel shovel that I use often, and when the blade finally snapped, they mailed me a new one for free.
One thing to note, the extra pound adds up for swings. If you are one-handed using this, you will get tired much quicker compared to the 3 lb Estwing sledgehammer. But, you can’t replace that extra 33.3% weight you get compared to the smaller hammer. I often use both hands combined with gloves to steady the swing and to ensure I don’t get gouged on the follow-through.
Husky 16 lb Sledgehammer
Cracking apart huge boulders is something I need to do with the local limestone here. The rocks are on average 9-15 inches thick and made of natural concrete-like limestone. I have a smaller older sledgehammer, with a wooden handle. It works, but I wanted something that I needed to hit the rocks with less. This thing is heavy and a chore to bring with me, but it’s often the best choice.
Fiskars sells the PRO 750640-1001 16lb sledgehammer with flat and wedge face for nearly double the price of the Husky. If I had my first choice, I’d likely go with the Fiskars as the wedge on the 4LB version has been fantastic. Keep in mind, checking out Amazon Reviews, there was a buyer who broke the head into two pieces after two years of use (J.D. Plooy 6/19/2019).
Other Useful Geological Tools
Aside from the tools to work rocks from the ground and to split and shape them with force, you often need special tools for further processing. When you find a good fossil, often the process is to use your hammer and separate it from a larger rock. However, this doesn’t always go as planned. To make more precision cuts in limestone or sandstone, I make use of two different angle grinders.
Angle Grinders and Diamond Wheels
Trying to pick the correct cutting wheels for limestone was confusing at first. I ended up with a 4-inch cutting wheel. It’s not as large as a 4 1/2 inch wheel, but it was the only Dewalt diamond wheel that was recommended for cutting granite, which is much harder than limestone.
I use three different cut-off tools. a 4 1/2 inch grinder, a 7 inch grinder and a 12 inch cut-off cutter.
Dewalt 4 1/2 inch angle grinder – DWE4120
This grinder was the first step in cutting rock. Being only 4 1/2 inches in depth from the center, you only get a little more than an inch of cutting. However, this can easily separate a specimen from the matrix for removal later. Making a clean cut can allow access for chisels to make a cut without removing a specimen visible on the surface. However, there are times where a deeper cut is necessary.
Dewalt 7″ angle grinder
To cut a bit deeper, I also bought a 7-inch grinder. Fortunately, corded versions of these are pretty inexpensive. I bought the 7-inch version of the same blades I used for the 4 1/2 inch. If I need to be sure I get a deeper straight cut, I’ll use this grinder. I did have to buy a specialty cutting wheel guard to be able to use this properly, so while the base unit was affordable, it will cost more to get up and running for cutting through rock.
Evolution DISCCUT1 12″ Disc Cutter
I originally bought this to make relief cuts to make a limestone sink. It did its job great. This is a powerful tool and draws a ton of power. It can make a 4 inch cut in limestone and other types of rock with the included 12-inch diamond blade. However, it just feels dangerous. There is a ton of power generated in the 12-inch blade and it cuts well.
Fossil Prep Tools
Once you get your fossil out of the rock in some shape, there are typically portions of it still buried in the matrix. There are a few schools of thought. Some like to keep the fossil natural, as found, and some like to remove all things from the matrix that traps them. Limestone is very tough as a matrix. When a sea creature is fossilized, the empty space typically is limestone with the shell acting as a barrier. The shell can be aragonite, calcite, or some other mineral that has replaced the original creature. The inside mold is called a steinkern.
Chicago Pneumatic CP 9361 Industrial Scribe and Engraving Pen
This is one of my favorite tools for prepping fossils. It is a miniature air-powered jackhammer that is used to remove or nip away at the rock surrounding the fossil. These are not cheap, typically costing between $250 and $300 depending on the market you are using to purchase. Occasionally they come up used, although a tool that gets used like this can be risky used.
The tool works by striking the surface up to 13,500 times per minute. The speed is adjustable, from a range of 1-5 by twisting the ring at the base of the tool. It comes with an extra carbide stylus and some additional ones. Included was a chisel shape and some blanks that can be shaped how you would like. I do find the one that comes with it best to work with and have not yet replaced it in the past year.