Magnetism

Image credit: Scott Brande

The Bottom Line on Magnetism - Here on Top!

Only one common mineral in most student kits is significantly magnetic, and that's natural magnetite. You don't need a magnet to identify magnetite. You just need an iron-containing object that a magnet would attract, like a paperclip. Magnetite is one of the few common minerals that can be identified with just one diagnostic property. Now that was easy, wasn't it?

Bottom Line: Using a paperclip to test a mineral for the magnetic property takes just a second. If a sample attracts a paperclip, then you've almost certainly identified magnetite. So why not test for magnetism first?

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Video Demo for Magnetism Test

Watch the video demonstrations below.

Instructions: The Magnetism Test

Background - Magnetism (actually "electromagnetism") is one of the four forces of nature (along with gravity and the strong and weak nuclear forces). There aren't very many minerals that exhibit magnetism, and the most common and well-known one is, of course, magnetite.

Perhaps counter-intuitively, we don't need a magnet to test a mineral for magnetism. All we need is a lightweight metal object made with iron, such as a steel paperclip.

Caution - The magnetic intensity within a sample of natural magnetite may vary greatly. So one side of a sample may exert a greater force of attraction on a steel paperclip than another. Test all different sides of the sample. Also, be aware that the strength of attraction may be much weaker than that of a typical kitchen magnet on the refrigerator.

Materials for test

  • mineral sample
  • steel paperclip.

Procedure for the test

  • Place the paperclip on a surface,
  • Move the sample close to, but not touching, the paperclip.
  • Hover the sample over the paperclip.
  • Turn the sample over to test different sides of the sample against the paperclip.

Possible test results and interpretation

The sample will either attract, or not attract, the steel paperclip.

  • The sample has no effect on the paperclip. We conclude that the sample is not magnetic.
  • The sample moves the paperclip without touching it, or the paperclip jumps to and attaches to the sample. We conclude that the sample is magnetic.