Fossil shark teeth are more than just ancient souvenirs from Earth’s prehistoric oceans—they’re also striking in appearance. Most range in colors from jet black all the way to pearly gray and shades of blue, green, and even white. These color variations aren’t random. They’re the result of complex chemical processes that take place over millions of years during fossilization.
In this article, we’ll break down the science behind what gives fossil shark teeth their unique colors—and why those colors can tell us a lot about where and how a tooth was preserved.
What Are Fossil Shark Teeth?
Before we dive into color, let’s talk about what fossil shark teeth actually are.
When a shark loses a tooth—something they do frequently throughout their lives—it may sink to the seafloor and become buried under layers of sediment. Over time, and under the right conditions, the organic material in the tooth is replaced by minerals from the surrounding environment. This process, called permineralization, is what turns a tooth into a fossil.
Minerals Make the Color
The colors in fossil shark teeth are the result of the minerals that seep into the tooth during fossilization. These minerals replace the original enamel and dentin with stone-like material, and depending on the type of sediment and minerals present, the tooth takes on a different color.
Here are some of the most common fossil tooth colors and what causes them:
- Black – One of the most common colors, often formed in sediments rich in iron sulfides or manganese dioxide. These minerals turn the fossil a deep black or charcoal gray.
Above is an example of a megalodon tooth with your typical black coloration. This specific specimen is from South Carolina
Photo Credit: Fossil Driven
- Brown/Tan – Iron oxides, like rust, cause a range of earthy tones from golden browns to reddish hues.
Above is an example of a megalodon tooth with a unique brown coloration. This specific specimen is from Georgia
Photo Credit: Fossil Driven
- Gray/White – In environments with fewer impurities and more phosphate minerals, teeth may appear gray, beige, or even chalky white.
Above is an example of a megalodon tooth with a beautiful gray/white enamel. This specific specimen is from Venice, Florida
Photo Credit: Fossil Driven
- Blue/Green – These rare colors often form under very specific chemical conditions involving trace minerals like glauconite or phosphate variants.
Above is an example of a megalodon tooth with a beautiful blue enamel. This specific specimen is from Bone Valley, Florida
Photo Credit: Fossil Driven
Above is an example of a megalodon tooth with a beautiful & uncommon green enamel. This specific specimen is from Bone Valley, Florida
Photo Credit: Fossil Driven
It’s important to note that the tooth’s color doesn’t come from the shark—it comes from the earth it was buried in.
The Environment Matters
The sediment type, groundwater chemistry, and even the climate where a tooth fossilized can affect its final appearance. For example:
- Teeth found in peat-rich environments or riverbeds may turn dark or black from organic-rich sediments.
- Clay-rich and desert environments might produce lighter, tan-colored teeth.
- Some marine sediments give fossils a bluish-green tint, depending on the minerals present.
Even two teeth from the same species and time period can look totally different if they were fossilized in different locations. Bone Valley, Florida, is a great example of this. But this rule can happen just about anywhere.
Does Color Indicate Age or Rarity?
A common misconception is that darker teeth are older or more valuable—but that’s not always true. I personally get this comment a lot and most people are usually very intrigued when I tell them that the color has nothing to do with how old a fossil shark tooth is.
Color doesn't directly reflect the age of a fossil. Instead, it reflects the geochemical environment it was buried. However, some colors are linked to specific formations or layers of sediment, so they can offer clues about the fossil’s origin.
For collectors, rare colors like blue, green, or golden brown might be seen as more desirable—especially when combined with other factors like size, preservation, and species. This is especially true when you look at megalodon teeth that come from the central Florida area, like Bone Valley.
What Color Can Tell Collectors
Collectors often ask about the color of fossil shark teeth because it can impact value, aesthetic appeal, and origin identification. Understanding the “why” behind the color helps you appreciate the tooth’s geological journey, not just its prehistoric past.
If you're shopping for fossil teeth, keep in mind:
- Darker colors usually mean the tooth came from riverbeds or organic-rich layers.
- Lighter or tan hues may suggest a drier or sandier fossilization environment.
- Vibrant or rare colors can be region-specific—and sometimes command a premium. Again, Bone Valley is one of said locations. Same with Peru or even Indonesia.
Conclusion
Next time you pick up a fossil shark tooth, take a closer look at its color. That shade tells a story—not just of ancient seas and powerful predators, but of the unique chemistry and geology that preserved it for millions of years.
From dark and mysterious to light and rare, fossil shark tooth colors are a fascinating blend of science and nature, making each one a true piece of prehistoric art.
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