Geology 12 – Dalesandro
Lab #4 – Sedimentary Mystery Rocks
Instructions:

Sit in your groups at one of the nine lab stations. You will be given
a handout with clues to the different types of sedimentary rock.
 Each lab station has one of the nine samples of “mystery sedimentary
rock”. Use the handout and your book to identify each specimen of
mystery rock (you will have 4 minutes per station). Try to get as
many correct as possible. Each sample only appears once, so you
can cross off those you think you have already found.
 At the end of the lab, you will have 5 minutes to investigate the “bonus rock” for
extra value – it’s another kind of one of rocks you have already looked at!
 Sketch each sample as you examine it and include the sketches with your lab
write-up.
Due Date: Friday, November 6th.
Value: 24 pts.
Lab write-up sections:
Purpose: To examine and identify nine samples of sedimentary mystery rock.
Materials: Samples of sedimentary mystery rock, paper, pencil, sedimentary rock
handout.
Procedure: Y.O.W.
Observations: Sketches of all nine mystery rock samples (maximum of four per
page).
Results: Table showing sample number and your guess as to which sedimentary
rock each sample represents.
Conclusion: Y.O.W.
Sedimentary “Mystery Rock” Sample Identification Sheet
Rock
Clues
Mudstone
Grains are tiny. Cannot be felt by
hand. Rock feels smooth. Layering
can sometimes be seen.
Sandstone
Made up of lithified sand. Grains
are large and can be felt by hand.
Limestone
Consists of calcium
carbonate sediments. No
grains, whitish color.
Coquina
Made from shells of small sea
creatures cemented together.
Conglomerate
Made up of cemented fragments
of rock. Fragments are rounded.
Coal
Dark rock made up of plant
material lithified over
millions of years.
Siltstone
Similar to sandstone but with
smaller grains.
Greywacke
Similar to sandstone but found in
unique colors such as grey or purple.
Sample
Number:
1
2
3
4
5
6
7
8
BONUS
Type of Rock:
ANSWER KEY
Sample
Number:
1
2
3
4
5
6
7
8
BONUS
Type of Rock:
Sandstone
Coal
Limestone
Mudstone
Coquina
Siltstone
Greywacke
Conglomerate