![Fission tracks in the mineral apatite, viewed under a microscope](http://static.sciencelearn.org.nz/images/images/000/004/818/full/ITV_AbsoluteDatingMethods_FissionTrackDating.jpeg?1674175894)
When uranium decays, subatomic particles split away. The particles leave tiny tracks in the crystal structure of minerals such as zircon and apatite.
Name: Fission track dating
Material used: Volcanic glass, zircon and other crystals
Age range: 10,000 to 500 million years ago
How it works: Measures radioactivity by counting tracks left in crystals by decaying uranium atoms