Dusting for Fingerprints
Sia and Sabina showed their party guests how to make fingerprints with ink and compare them. They explained that each person has unique fingerprints.
That’s why detectives look for fingerprints at a crime scene. If they find fingerprints and can match them to their owner, that can help them identify who was at the scene! How can we find and identify fingerprints? Our skin produces natural oils. When we touch objects, some of this oil is left behind. It shows up as fingerprints. That’s why we can find fingerprints by “dusting” for them. Try this fingerprint dusting activity on your own or with your friends!
Supplies You Will Need:
- Hand lotion (optional)
- Cornstarch
- Small paintbrush
- Cellophane tape
- Black construction paper
Instructions
- Rub some hand lotion into your fingers. You can skip this step if you want, because you have natural oil in your skin and can leave fingerprints without the lotion—but using lotion will make it easier to find your prints!
- To leave fingerprints, touch a flat surface, such as a table, with your fingertips.
- Sprinkle a bit of cornstarch onto the prints. You should be able to see them.
- With a small paintbrush, gently brush away the extra starch, leaving only the starch that is sticking to your fingerprints.
- Carefully place a small amount of tape on top of one fingerprint. Use it to lift the starchy print off the table.
- Place the tape on a piece of black construction paper so you can see the fingerprint clearly. Repeat for all the fingerprints!
Fact: Even identical twins do not share the same fingerprints!
