Radioactive Methods for Age Determination

The rate of radioactive decay of some unstable elements is supposed be constant and independent of chemical state and environmental factors such as temperature and 

Nuclide Half-life Years Effective range for age determinations. Years Materials studied 

238u- 4 206pt 4.47 10 104 -10 Zircon, uraninite, Monazite, titanite 

The table contains actual figures (for 2002) compiled by A. Johansson. Swedish Museum of Natural 

The long half-Hves of the first six examples make dating of very old minerals possible, even an estimation of the age of the earth. The method for investigating old 

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