The method commonly used to record dates of artifacts and structures is Radiocarbon dating, and was pioneered in 1949 at the University of Chicago by William Libby who has since been awarded the Nobel Prize in Chemistry for his work. Radiocarbon dating accurately records dates to 58,000 years and was used to determine the date of the Bosnian Pyramids.
Italian archaeologists Dr. Ricarrdo Brett and Niccolo Bisconti discovered an organic material (a leaf) on the top of the concrete blocks that cover Bosnian Pyramid of the Sun in June 2012. Carbon dating was performed in Lab in Kiev, Ukraine with astonishing result: 24.800 years +/- 200 years.
It gives the minimum age of the pyramid structure and makes it the oldest pyramid in the world.