How to Check If a Fossil is Real or Altered?


Fossils are a fascinating sign of the past; they’re remains of organisms—both plant and animal—that existed many years ago. They can be studied to learn more about the type of creature, its origins, appearance, diet, and much more.

Sometimes however, due to centuries of wear and tear, fossils are barely more than scraps; other times they’re partially intact but otherwise damaged. Depending on the condition in which it was found, or the purpose it’s being kept, a fossil can also be altered in order to restore it.

What is the difference between a ‘real’ fossil and an ‘altered’ fossil?

More often than not, fossils don’t remain in their original shape or form. They undergo several processes over time, being affected by environmental factors, other creatures, being fed on, so on and so forth.

How to Check If a Fossil is Real or Altered?

There are different forms of alteration, both natural and artificial. Most commonly, permineralization and petrification are the types of alteration that occur. It’s when harder materials such as bone, shells and plants are penetrated through groundwater. Eventually through different materials such as silica, the original hard structure is preserved.

Carbonization is another common chemical reaction wherein the pressure of the rocks causes gases to release, leaving behind only a film of carbon that resembles outlines of the original organism. Another process is recrystallization, which leads to the original substance changing its form.

We also often see molds and casts that naturally encase and preserve the fossil. And one of the most common images of fossils is of those preserved in amber.

As we’ve mentioned, often in an attempt to restore the fossil to how it originally should have been, it’s altered using different materials and techniques on purpose. Some of the materials used are:

  • Plaster
  • Clay
  • Rocks
  • Petroleum jelly

While alteration of fossils is part of their preservation, it’s also worth watching out for when purchasing.

The different degrees of repair and restoration

When it comes to the repair and restoration of a fossil, there are varying levels and degrees, intents and purposes for doing so.

How to Check If a Fossil is Real or Altered?

More often than not, it’s a result of damage to the fossil, or being unable to find the missing parts.

For collectors, museums and other places where these fossils are up on display, it makes sense to have a restored or repaired fossil.

Sometimes it’s just ‘improved’ in order to give it more finesse. You can find out the restoration percentage before making a purchase, or watch out for artificial materials. However, it’s not always easy for laypeople to spot those.

When buying a fossil, be sure to ask your seller to check for discrepancies in the region and date provided by them. At Two Guys Fossils, we only deal in genuine dinosaur fossils for sale online in East Bridgewater, so you can rest assured when it comes to the quality of our products. You can find those and our collections of trilobites, fish fossils for sale, and many other types at our best online fossil store