Judging by color in the early history of geology and paleontology

This paper presents an overview on some significant historical sources, particularly from 17th to 18th century Italian scientific literature, in order to understand how color was used as one of the ‘external’ features for identifying rock formations, also including fossils, regarded as having formed in different times by different causes or events. The reference to color was also considered the main feature used for lithostratigraphical purposes within the so called ‘classifications’ of mountains in the second half of the 18th century. Later geologists and mineralogists involved in the early development of stratigraphy referred to color when a rock formation or specimen appeared to be less distinguishable by other main characters (for example chemical and morphological features).