Scientists at Texas A & M University have developed a new technique to carbon date pictographs on limestone, as long as there is an organic component to the paint layer. The datable carbon is isolated from the carbon in the limestone by introducing a painted sample to oxygen and then converting the gas to oxygen plasma with a radio frequency generator. If organic material containing carbon is present in the sample, the reaction will produce water and carbon dioxide. The carbon dioxide may then be datable by an accelerator mass spectrometer.