FOSSILIZATION LAB
NAME
HOUR
KNOWLEDGE TAG: s3o2e
INSTRUCTIONS: Please follow along with the first lab example and then do the other 2 stations with a
partner.
PETRIFICATION MODEL
This one we will do together.
1.) Observe the process and describe it.
2.) What represents the bone or wood?
3.) What represents the minerals in ground water?
4.) What type of fossilization does this model?
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PIPE CLEANER BUG
3 x 5 index cards
Hot glue gun and glue sticks
Brown pipe cleaners or actual insects
STEP 1: Take a small pipe cleaner, make a small insect with it, and place it on a 3x5 card.
STEP 2: Very carefully place a large drop of glue on the small pipe cleaner so that the pipe cleaner is
completely covered/encased.
STEP 3: Let it cool.
STEP 4: Please clean up any mess.
Questions
1.) What represents the insect?
2.) What represents the amber?
3.) What type of fossilization is this?
4.) How is this similar to actual fossils?
5.) How is this model similar and different from actual fossils?
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MAKNG TRACKS
STEP 1: Mix a 1⁄2 cup of dry Plaster of Paris and approximately a 1/4 cup of water. Mix it together and let it
set for about 5 minutes.
STEP 2: While you are waiting the few minutes, choose a fossil from the jar. Use a small amount of Vaseline
and cover the fossil.
STEP 3: After a few minutes place the “vaselined” fossil onto the plaster of paris mixture. Very gently press it
into the mixture. Let it sit for about another 10 minutes.
STEP 4: After the 10 minutes or so, gently pry out the fossil.
STEP 5: Put a very small amount of Vaseline on the first layer.
STEP 6: Mix another batch of plaster in a separate cup and pour it over the first layer.
STEP 7: put your name on it and put it with your insect fossil in a cubby under the lab tables.
Questions
1.) What represents the fossil?
2.) What represents the rock/sediments?
3.) What type of fossilization does this represent?
4.) How is this similar to actual fossils?
5.) How is this model similar and different from actual fossils?
Makin Tracks
Pipe Cleaner Bug
Sponge Fossil
Describe the processs/steps you
did at this station
Describe the processs/steps you
did at this station
Describe the processs/steps you
did at this station
What type of fossilization does
this represent?
What type of fossilization does
this represent?
What type of fossilization does
this represent?
Similarities (list 2)
Differences (list 2)
List 2 things you learned about fossilization in this activity
Bag of Plaster of Paris
Bowl and spoon
Water
8 oz. paper cup
Measuring cups
Plastic fossils and bird feet
Petroleum jelly
Paraffin wax
Activity 3: Permineralization
LET'S MAKE A FOSSIL #1
Summary:
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.
Instructional Method: Activity
Goal: To teach students how permineralized fossils form.
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.
Time:
Setup: 15 min.
Presentation: 30 min.
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
Vocabulary:
calcium carbonate
crystal
decompose
dissolve
fossil
permineralize
petrified
pyrite
replacement
saturate
silica
Background:
Permineralized fossils, such as petrified wood, are often some of the most beautiful fossils. They are often
filled with multicolored crystals. The various colors can be traced to specific types of mineral impurities
(reds = iron, greens = copper, yellows = sulfur, etc.).
Jorge Dauerer
Sections of petrified wood.
Most found dinosaur bones are permineralized. Permineralized fossils are created when spaces in an
organism that usually hold liquids or gasses are filled with mineral rich water. This happens both in an entire
organ like a lung and inside individual cells. As mineral rich water concentrations increase, those minerals
precipitate out, filling the voids and surrounding the cell walls and cell membranes. Examples of minerals
that commonly dissolve and saturate in solution include silica (SiO2), calcium carbonate(CaCO3), and iron
ores like pyrite (FeS2).
Eventually, all carbon-based tissues will rot, completely decomposing. But through a complicated chemical
process called replacement, even things like cell walls and cell membranes can be preserved by trading their
carbon molecules for rock forming minerals. When this happens, a large amount of biological detail is
preserved, especially when the replacing minerals differ from minerals that caused the permineralization. For
example, when silica-rich water is the permineralizing agent and iron pyrite replaces the tissues,
paleontologists can see internal cellular structure. They can even distinguish between different cell
organelles! This is only possible when the fluid space within individual cells is also permineralized. This
high quality form of permineralization is called petrifaction and commonly occurs in petrified wood. So to
be petrified, objects end up containing none of their original chemistry.
Although permineralized fossils are usually the most durable fossil type, they are not impervious. Extreme
heat and/or pressure created by igneous or metamorphic processes can dissolve and melt them. Rainwater,
being slightly acidic, will dissolve fossils permineralized with calcium carbonate. Furthermore, the same
mechanical weathering that exposes them from their surrounding rock will also eventually destroy them.
Permineralized fossils are highly sought after by both rock hounds and paleontologists. While
paleontologists value these kinds of fossils because of the detailed biology they record, collectors like them
for their beauty and durability.
In this activity the sponge represents animal bone and the paraffin wax is the permineralizing agent.
NPS
three sponges that represent what can be used to create fossils
Instructional Procedures:
1. Present background information to students.
2. Pass out sponges, fossil stencils, and markers.
3. Instruct students to use the stencils to trace the shape of a fossil of their choice or encourage them to
draw one of their own design.
4. Have students cut fossil shapes out of their sponges.
5. Instruct students to write their names or initials on their fossil to prevent ownership confusion later.
6. Cut a large enough piece of wax paper to accommodate the cooling of all the sponge fossils.
7. Place paraffin block(s) in a pot on high heat. Add just enough water to keep the wax from burning
(usually ¼ cup per block of paraffin is sufficient).
8. Put on rubber gloves and safety goggles.
9. Bring wax to boil and then back the heat off to minimize hot wax splatters.
10. Use tongs to submerge each sponge fossil for 5-10 seconds in the boiling wax. Squish the sponges so
that every pore absorbs wax.
11. Place each sponge fossil onto the wax paper for cooling, being careful not to squeeze the sponge, or
some of the wax will be lost from the sponge.
12. Once cool, return the sponge fossil to the owners for their inspection. What once was soft and
squishy should now be hard and brittle.
Discussion:
Ask students to explain how permineralized fossils form using either the sponge example or one from real
life. Encourage the students to speculate as to what will happen to their sponge if it gets hot again or exposed
to water. Help them draw analogies as to what natural processes can destroy real permineralized fossils.
Variations:
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:
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.