Complete Article, courtesy USGS.
Forensic, Art, and History Studies – Calcareous nannofossils have been used to help police solve criminal cases. For example, clay scraped from the shoes of a murder suspect in England contained calcareous nannofossil species that were unique enough to lead the police to the scene of the crime. Calcareous nannofossils have been used to determine the origin of building stones for Medieval churches in Denmark and to check authenticity of paintings. In Norway, which has no native chalk, calcareous nannofossils were used to determine the origin of white chalk that was used to prepare the surfaces of Medieval wooden sculptures and panels before painting. The pattern and changes through time of the chalk trading routes probably can be used to interpret general trading patterns in northern Europe at the same time.
Source of interest: SCHULTE, P., R. SPEIJER, H. MAI, AND A. KONTNY. 2006. The Cretaceous-Paleogene (K-P) boundary at Brazos, Texas: sequence stratigraphy, depositional events and the Chicxulub impact. Sedimentary Geology, 184:77-109.