The rock samples are crushed, in clear gear, to a measurement that preserves whole grains of the mineral to be dated, then sieved to assist focus these grains of the target mineral. The selected measurement fraction is cleaned in ultrasound and acid baths, then gently oven-dried. The goal mineral is RussianCupid help separated using heavy liquids, then hand-picked beneath the microscope for the purest potential sample.
Using the principle of faunal succession, if an unidentified fossil is found in the same rock layer as an index fossil, the two species must have existed during the same period of time (Figure 4). If the same index fossil is discovered in different areas, the strata in every space had been likely deposited on the similar time. Thus, the principle of faunal succession makes it attainable to determine the relative age of unknown fossils and correlate fossil sites throughout large discontinuous areas.