4th Century BC Geology
Aristotle made some critical observations of the slow rate of geological change. He observed the composition of land and formulated a theory. This theory is one of the first evidentially based concepts connected to the geological realm that the Earth is physically changing.
Following Aristotle’s successor, Theophrastus, who made the greatest progress in geology through his work, On Stones. He described many minerals and ores from Laurium near Athens. Also, he studied about the classification of minerals based on its hardness.
Piny the Elder produced a very extensive discussion of many minerals and metals that later on became widely used. He was among the first to correctly identify the origin of amber as fossilized resin from trees.