Types of fossil
There are many different types of fossils - it’s not just bones and teeth that fossilise. Read through the information below to discover some of the different types of fossil we can find.
Mould and Cast Fossils
Ammonites were squid like creatures living in the sea inside spiral shells. They went extinct at the same time as the dinosaurs, approximately 65 million years ago.
Some fossils are called mould and cast fossils. A example of a mould and cast fossil in the GeoBus collection is our ammonite fossils. Watch the video below to discover how an ammonite fossil is made.
A mould and cast fossil is made when water dissolves the buried shell or bone. This will leave behind a hole in the shape of the shell or bone in the surrounding rock. This is a mould.
Over time minerals or sediment fill this mould and create a fossil in the shape of the original bone or shell, known as a cast fossil.
Have a look at the 3D ammonite fossil below and use all the information to create your own fact card on mould and cast fossils.
Trace Fossils
Trace fossils such as footprints are made in a similar way to mould and cast fossils. The footprint creates a hole in the rock which becomes a mould. Sediment then fills the mould to create a trace fossil.
There are lots of different types of trace fossil such a nests, bite marks, footprints and coprolite (droppings!). Have a look at the 3D footprints below and use all the information to create your own fact card on trace fossils.
Resin Fossils
Resin fossils are made when small animals or insects become stuck in sticky tree resin. Over time the resin will harden and become amber.
Have a look at the 3D mosquito in amber model below and use all the information to create your own fact card on resin fossils.
Optional Activity
Fact Cards and Fossil Making
Using paper and colouring pens/pencils, create fossil fact cards showcasing each of the different types of fossils.
If you are looking for more information you can find a recap of the different types of fossils and how they are formed in the worksheet below. It also includes instructions for how to make your own fossil at home!
You can also download and print our ‘Fossil Box’ to store and keep your GeoBus fossil safe.