Although similarities between fossils and living organisms could clearly be perceived, it did not, to Plot, necessarily follow that the one had come from the other. According to the neoplatonic school of thought, the whole cosmos is a web of hidden affinities, made visible in the resemblances between Man and his external world, between the heavens and the Earth, and between living and non-living entities. Neoplatonists could therefore attribute organic resemblances to the action of a pervasive moulding force or “plastic virtue” that governed the growth of living organisms, but also operated within the Earth. For Plot, this “plastic virtue” was crystallization, which he felt capable of remarkable feats:

Not all the fossils known to Plot were explained by the action of a “plastic force”. Having described fossils resembling the human brain, eyeball, ear, heart and kidney, he came to an object of particular strangeness: Plot decided, on the basis of the internal structure, that this specimen was indeed a petrified bone but, given its great size, what animal could it have come from?

Stage 1: A dinosaur dies and is buried before the remains are completely destroyed.

Stage 2: Over time, layers of sediment build up and press down on the buried remains.

Stage 3: Dissolved minerals, transported by ground-waters in the sediment, fill tiny spaces in the bones. The combination of pressure, chemical reactions and time eventually turns the sediments into rock and the bones into mineralised fossils.

Stage 4: The fossils remain within the rock until uncovered through erosion or excavation.

https://www.livescience.com/37781-how-do-fossils-form-rocks.html

https://science.howstuffworks.com/environmental/earth/geology/fossil3.htm