Radiocarbon dating timescale

A Western bristlecone pine trees can live up to 5000 years scientists can precisely determine the age of a tree by counting the annual rings in its trunk. The trees can therefore be used to cahbrate the timescale for radiocarbon dating. 

For timescales spanning the last 50,000 years, radiocarbon dating is one of the most widely used dating techniques. It can be applied to organic material, biominerals (such as shell and coral), and in some cases to carbonate deposits and is therefore possible in a wide range of different environments. It is complementary to other techniques such as optically stimulated luminescence... 

Stuiver, M., Radiocarbon timescale tested against magnetic and other dating methods, Nature, 273, 271-274 (1978). 

Richards, D.S., Beck, J.W., Donahue, J.W., Smart, P.L. and Edwards, R.L., 1999, Th-230 and C-14 dating of speleothems from the Bahamas Implications for the calibration of the radiocarbon timescale, in Ninth Annual V.M. Goldschmidt Conference, LPI Contribution No. 971, Lunar and Planetary Institute, Houston, p. 245. 

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