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Isotopes
Commonly used for Radiometric Dating
| Isotopes | Half-life (years) |
Effective Dating
Range (years) |
|
| Dating Sample | Key Fission Product | ||
| Lutetium-176 | Hafnium-176 | 37.8 billion | early Earth |
|---|---|---|---|
| Uranium-238 | Lead-206 | 4.468 billion | 10 million to origin of Earth |
| Uranium-235 | Lead-207 | 704 million | 10 million to origin of Earth |
| Rubidium-87 | Strontium-87 | 48.8 billion | 10 million to origin of Earth |
| Potassium-40 | Argon-40 | 1.277 billion | 100,000 to origin of Earth |
| Carbon-14 | Nitrogen-14 | 5730 40 | 0-100,000 |
| Note:
the half-life durations listed in the text
sections of this tutorial are
rounded off for uranium-238 and potassium-40. |
Copyright 1999-2012 by Dennis O'Neil. All rights reserved.