If the rock contains organic material, they can use carbon dating to find out how much carbon is left to determine the age.
since they are not actually rock but very old cheese it is sometimes hard to tell their exact age. Scientists however speculate that they are between 1200 and 1800 years old.
with your eyes
Scientists call lava the newest rock on earth because it hasn't even cooled into igneous rock yet, making it effectively 0 days old.
What environment did the sedimentary rock form in? What processes led to the formation of this rock? Are there any fossils present in the rock and what do they reveal about the past environment? How has the rock been altered over time through diagenesis or tectonic forces?
Relative dating
== NO a fossil must be found but scientists can probably guess about how old the mountain is by looking at it and fing== ding out the types of rock that it has. ===
Fossils in rock layers can be used for relative dating, where older fossils are found in lower layers and younger fossils in higher layers. By comparing the fossils in different layers to known fossil sequences, scientists can estimate the age of the rocks. Fossils provide a timeline of life on Earth and can help determine the relative ages of rock layers.
You can determine the relative age of a fossil by looking at the position of the fossil in the rock layers. The closer a fossil is to the surface, the younger it is relative to fossils found deeper in the layers. To determine the absolute age of a fossil, scientists use radiometric dating techniques on the surrounding rocks to determine the age of the rock layer the fossil is found in.
over millions of years old
Old state house Museum, the old mill in Little Rock(look up little Rock old Mill),and the Toltec Mounds
Index fossils are useful to geologists as they are distinctive fossils that can be used to date the age of rock layers based on their known age ranges. By identifying and studying index fossils in rock layers, geologists can determine the relative age of the rocks and establish a timeline of Earth's history. This helps geologists correlate rock layers across different locations and construct a more accurate geological history of an area.
Some would argue that it (old age) is a state of mind.