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The same applies to archeological sites, containing rock art like cupules, petroglyphs, pictographs and other prehistoric works.Thus this list of the earliest art by our ancestors like Homo erectus, Homo heidelbergensis, Homo neanderthalensis, and Homo sapiens sapiens - should be seen merely as a snapshot of an ongoing process of discovery.Fission-track dating is a relatively simple method of radiometric dating that has made a significant impact on understanding the thermal history of continental crust, the timing of volcanic events, and the source and age of different archeological artifacts.The method involves using the number of fission events produced from the spontaneous decay of uranium-238 in common accessory minerals to date the time of rock cooling below closure temperature.in natural minerals, the use of laser ablation inductively coupled plasma mass spectrometry for measuring uranium concentration for apatite and zircon fission-track chronometry, and detrital thermochronology based on measuring Nd isotopic compositions on single apatites by laser ablation ICP-MS, to cite a few examples.

At present, a large variety of fossils, tools and artifacts are being studied by paleoanthropologists and other Stone Age scholars, in order to fix their date of origin.

(removal of material by solution) of the host substance with a suitable chemical reagent; the leaching process allows the etched fission-track pits to be viewed and counted under an ordinary optical microscope.

The amount of uranium present can be determined by irradiation to produce thermal fission of .

Only recently (2012), we have seen the chronology of Paleolithic art and culture changed completely by Uranium/Thorium dating tests on the cave art of El Castillo and Altamira.

In addition, it seems likely that Aboriginal rock art in Australia will also - in the not too distant future - be discovered to be much older than presently thought.