Types of Fossils

Trace Fossil

A trace fossil is a mark, footprint, trail, burrow, or any other trace of a plant or animal.

This is a trace fossil of an animal's burrow.

Trace Fossil: Burrow

This is a trace fossil of an animal's footprint.

Trace Fossil: Footprint

Mold Fossil

A mold fossil is formed when an organism dies and is covered by sediment, creating an impression.

This is a mold fossil of a seashell.

Mold Fossil: Seashell

This is a mold fossil of a leaf.

Mold Fossil: Leaf

Cast Fossil

A cast fossil is formed when minerals fill the inside of a mold fossil, creating a 3D model of an organism.

This is a cast fossil of a seashell.

Cast Fossil: Seashell

This is a cast fossil of a bug.

Cast Fossil: Bug

True Form Fossil

A true form fossil is a fossil of the real plant or animal part.

This is a true form fossil of a bug.

True Form Fossil: Bug

This is a true form fossil of a spider.

True Form Fossil: Spider