Radiometric dating is also used to date archaeological materials, including ancient artifacts.
Different methods of radiometric dating vary in the timescale over which they are accurate and the materials to which they can be applied.
It is estimated that nearly 90% of all measurements made at the more than 50 active accelerator mass spectrometry laboratories are radiocarbon dates.
This dramatic increase in the number of radiocarbon dates is driving the demand for a radiocarbon calibration program that spans the entire radiocarbon timescale from the present to 55,000 years BP.
Background We think of a battery today as a source of portable power, but it is no exaggeration to say that the battery is one of the most important inventions in the history of mankind.
Volta's pile was at first a technical curiosity but this new electrochemical phenomenon very quickly opened the door to new branches of both physics and chemistry and a myriad of discoveries, inventions and applications.
When more finds came to light with what also appeared to be rickets, it was considered far too much of a coincidence and for lack of any other explanation they became relegated to a sub-human category.
To access our radiocarbon calibration program, click on the 'Radiocarbon Calibration Program' button above, or here.
They did not have the benefit of cheap, off the shelf, mass produced batteries. Bronze is a relatively hard alloy of copper and tin, better suited for the purpose than the much softer copper enabling improved durability of the weapons and the ability to hold a cutting edge.
For many years the telegraph, and later the telephone, industries were the only consumers of batteries in modest volumes and it wasn't until the twentieth century that new applications created the demand that made the battery a commodity item. The use of bronze for tools and weapons gradually spread to the rest of the World until it was eventually superceded by the much harder iron.
BP using coral samples from our offshore coral reef core collections from Barbados (13.10°N; 59.32°W) in the western tropical Atlantic and Kiritimati Atoll (1.99°N, 157.78°W) in the central equatorial Pacific, and from the uplifted reefs of Araki Island (15.63°S; 166.93°E) in the western Pacific.
In addition, we have reanalyzed the radiocarbon and U age dates from our earlier radiocarbon calibration work using new pretreatment and analytical techniques and state-of-the-art instrumentation at higher precision; we report these new results in this WEB site and in Fairbanks et al., (2005).