Permineralization: making a fossil

This resource teaches a way to for students and teachers to make fossils besides a mold or cast method. The materials are regular non-abrasive kitchen sponges and paraffin wax. The method describes could be adapted for all ages of students.  Fossils are remnants of once living things. One way fossils form is by permineralization. This is when the pore spaces of a bone are filled with mineral rich water and internal crystals begin to form. Eventually the whole bone becomes rock. The activity uses a sponge dipped in wax to imitate permineralization.

Weblink address (URL): 
Permineralization: making a fossil

Standards & Objectives

Learning objectives: 

Students will be able to:

  • Make a comparison between their new wax sponge fossils and how mineral rich water crystallizes in the pore spaces of an organism's bones.
  • List the steps in how a bone becomes permineralized.
  • List organic body parts besides bones that can become permineralized.

Lesson Variations

Blooms taxonomy level: 
Applying
Differentiation suggestions: 

Add different colors of food coloring to multiple pots of boiling wax to simulate different kinds of mineral impurities. As directed by the students, dip different portions of the sponge fossil in different colors of wax. Alternatively, experiment with squeezing the sponge in one color and then just quickly dipping in another, in an attempt to simulate different internal permineralization.

Extension suggestions: 

Have the students cut out their fossils so that the leftover portion of the sponge is one intact piece. Use the internal portion of the sponge and the external border to illustrate the concept of molds and casts. Tour a museum or natural setting where various kinds and colors of permineralized fossils can be observed. Initiate and guide a discussion about the conflict created between souvenir hunters / rock hounds and paleontologists. Explain how permineralized fossils are exceeding in value to both groups of people yet for entirely different reasons. Invite the students to come up with ideas and policies that might satisfy both kinds of people's needs.

 

Helpful Hints

Materials needed:

Paraffin wax, 1 block (2" x 2" x 6") per 10 students 1 Nonabrasive household sponge per student (the bigger, the better) Heat source and a pot/pan for boiling paraffin wax Rubber gloves and safety goggles Tongs Permanent Markers and Scissors Various colors of food coloring (optional) * Stencils of different fossil shapes download file Wax paper

 

References

Contributors: 
Jennifer Hassell
Originator: 
Ayers Institute for Learning & Innovation