Electricity Rocks!by Jordan Scherr

November 7, 2013

Question:

Are rocks conductors?

What are conductors?Conductors are different types of metal that light up the bulb in the tester.

Materials• Rocks:

Iron pyrite, ore, white geode, purple geode, peacock rock, tiger eye, agate

• Tester: Tape, wires, bulb, D cell

• Example conductors: Tin foil, coins

How the tester worksYou can’t see it, but the bulb is touching one terminal of the battery and a wire is touching the other. The other wire is touching the side terminal of the bulb. When you touch both wires to a conductor, the bulb will light up, because it will be a complete circuit.

SetupHere we have proof that the tin foil and coins are conductors. We touched one wire to the tin foil and the other to the top of the coins. The bulb lit up, meaning these are conductors.

PredictionI was thinking that the iron pyrite would be a conductor because it has “iron” in its name. I thought that none of the other rocks would be conductors.

Measured and controlled variables

Controlled variables: We used the same wires, D cell, tape, and bulb.

Measured variable:We changed the type of rock.

Observations

I did three trials for each rock and I observed that the peacock rock and the iron pyrite both lit up.

AnswerMy prediction was partly right and partly wrong. The iron pyrite did light up, but the peacock rock lit up too.

New questions ... and answersWhy did the peacock rock light up? Is it because it has some type of metal in it?

Internet research: Peacock rock is almost completely metal. It has a lot of copper and iron in it.