Some of mankind’s oldest and best tools are fire and knives, and descended from the knife are all sorts of other cutting implements from axes to arrowheads.
It turns out, there is one all-natural material that has been with us basically from the beginning in the form of flint.
Flint is basically a type of sedimentary rock, a high-quality type of quartz that’s extremely hard with predictable and useful fracturing patterns.
And also makes sparks when it is struck against hard metallic surfaces. Together, this can cover a lot of your bases when it comes to survival requirements!
And best of all it’s free, assuming you know where to look out in the world.
Finding flint might very literally save your life in a survival situation, so keep reading and I’ll tell you everything you need to know when it comes to finding a deposit and then positively identifying it.
What is Flint, Exactly?
Flint is a type of sedimentary rock, and more specifically a type of cryptocrystalline quartz. It is known for being extremely hard, being made from solidified silica particulates, but incredibly fine-grained.
It’s actually formed from the massed remains of tiny marine organisms called diatoms (among others), which have built up over millions of years.
When you strike a piece of flint against steel, the friction produces a spark that can ignite dry tinder. This unique characteristic makes flint an essential tool for wilderness survival.
It’s perhaps most known for its ability to generate sparks in conjunction with steel and other materials, making it highly prized in the days before modern matches and lighters came along.
It can also be used to make incredibly sharp, if fragile, edged tools. It is still just as useful- and viable- for those purposes today!
Where is Flint Found Around the World?
Flint can be found all over the globe in various places, but it’s most commonly associated with chalk deposits.
It’s also especially prevalent in certain regions of North America, Europe, and Asia.
The key thing to remember is that flint is typically found in areas that were once underwater, where countless generations of those tiny diatoms lived and died before being compressed into the mineral we know today.
If you’re going out to search for flint, do your research: you might want to start in regions known for their ancient marine environments, or any area near a flood plain or river.
Where Can You Find Flint Geologically?
Geologically speaking, flint is usually found in layers within limestone or chalk formations. These rocks are typically located in or near former ocean beds or major other bodies of water as I said above.
This means you might find it in riverbanks or along the coastline where erosion has washed it from its original location.
Where are the Best Places to Find Flint in the U.S.?
The United States is positively blessed with rich flint deposits, with locations in over two dozen states.
If you’re in the Midwest, Flint Ridge in Ohio is the most famous spot, named for its gargantuan formation of unique, red flint.
For those in the Northeast, Pennsylvania and Virginia offer several known flint deposits in several different counties.
In the South, Georgia and Mississippi have ample flint resources to find, and you can almost always find some no matter where you are if you look hard enough.
Even out West, Colorado’s wild spaces are absolutely ripe with flint.
Closer to developed areas, don’t forget that construction zones and gravel roads can also be prime flint-hunting grounds: anywhere you find disturbed earth and broken rock there is a chance of finding flint.
The trick, as always, is identifying it!
What are You Looking For?
When searching for flint, it is an exercise in alertness and keen-eyed observational skills. To make the hunt easier, and avoid having to sift through rocks all day, look for its distinctive characteristics.
Flint has a somewhat glassy texture (like obsidian, but less so) and often forms as “nodules” inside chalk or limestone deposits.
Pay close attention to the texture and sheen as flint will be waxy and opaque-looking, but more translucent at the very edges.
Also, look out for a “glimpse” of flint on a rock: be ready to clean this prime suspect because it’s usually flint encrusted with calcium, concealing its actual characteristics! If the calcium brushes or chips off easily, you are on the right track.
In terms of color, it can range from black or grey to brown or white, or even sort of fade or modulation of those colors.
One surefire way to identify flint is by striking it against steel. If it produces a spark, you’ve likely found yourself some flint!
What Determines the Color of Flint?
Flint’s color is determined by the impurities it contains and the environment in which it was formed. Iron compounds, for instance will lend flint a common reddish-brown hue.
If the flint was formed in an environment with a lot of organic matter, it might be darker, often appearing black or a smoky dark gray.
Conversely, flint formed in chalky environments can be lighter, ranging from light gray or tan to near-white. Remember, though, that no matter its color, flint will always spark when struck against steel.
Is Flint Opaque or Translucent?
The translucency, or lack thereof, is a common cause of consternation when assessing flint. One way to identify it is by its opacity.
Unlike some minerals, flint is largely opaque. That means you can’t see through it, even when you hold it up to the light.
However, very thin pieces of flint, or the thin edges of flint, may allow a little light to pass through, giving it a slightly translucent edge.
So, if you find an opaque rock with a waxy, glassy texture, you might have yourself a piece of flint.
Flint Can Also Knap Easily and is Very Sharp!
Another unique property of flint is its ability to knap, or break in a way that allows you to shape it into useful tools.
When flint fractures, it fractures conchoidally, a Scrabble Tournament-winning word used by rockhounds to mean “smoothly, roundly and in the manner of a scallop”.
Said simply, it looks like a little scoop of the rock was taken out. This property allows the controlled and easy creation of sharp edges.
This is what made flint an essential resource for our ancestors, who used it to craft all kinds of cutting tools and weapons, arrowheads foremost among them.
How Can You Test to See if You Have Flint?
Now that you’ve found a potential piece of flint, how can you be sure? Visual ID based on color or texture alone is tricky. One reliable method is to perform a spark test.
Take your rock and strike it against a piece of steel, or vice versa: If you see sparks fly, congratulations, you’ve likely found flint!
This happens because flint is harder than steel, allowing it to scrape off tiny particles of the metal which ignite in the air. But do remember; always take care when striking rocks as they can create sharp fragments.
Another method is to try breaking it yourself: by carefully striking or pressing suspected flint with a round, sturdy tool you might reveal those scallop-shaped fractures I detailed in the previous section. Or your piece might already be fractured in this way, so look closely.
Lastly, try a simple hardness test: take the back of a knife or a nail point and try to scratch the flint. Be careful not to use so much pressure it fractures.
If it doesn’t scratch, you’ve got a dang-hard rock. It might be flint, but it could also be common quartz. Most rocks are softer than steel and will scratch.
Is Flint the Same Thing as Chert?
If you’ve looked into this topic at all, you might have seen the term chert come up more than once. Sometimes it seems like it is used interchangeably with flint.
Are they the same things? Yes, but no. Well, they are very similar!
Both flint and chert are types of microcrystalline or cryptocrystalline quartz. They share many properties discussed already, including hardness, conchoidal fracturing, and the ability to generate sparks when struck.
However, there’s a slight difference in their formative characteristics: Flint is basically a high-quality, opaque subtype of chert. So, while all flint is chert, not all chert is flint.
Tom Marlowe practically grew up with a gun in his hand, and has held all kinds of jobs in the gun industry: range safety, sales, instruction and consulting, Tom has the experience to help civilian shooters figure out what will work best for them.