Atom probe tomography analysis of mica Cappelli, Chiara Pérez Huerta, Alberto Alam, Sardar B. Prozorov, Tanya 3D reconstruction Anisotropy Biotite This research was funded by the U.S. National Science Foundation (NSF), grant numbers EAR-1647012 and EAR-2019870. T.P. and A.B.S. acknowledges support of Laboratory Directed Research and Development Program through Ames Laboratory. Microscopy work (FIB-SEM and STEM imaging) was performed using instruments in the Sensitive Instrument Facility at the Ames Laboratory, which is operated for the U.S. DOE by Iowa State University under contract # DE-AC02-07CH11358. Finally, this study utilized resources owned and maintained by the Alabama Analytical Research Center (AARC), supported by The University of Alabama. Laser-assisted atom probe tomography (APT) is a relatively new, powerful technique for sub-nanometric mineral and biomineral analysis. However, the laser-assisted APT analysis of highly anisotropic and chemically diverse minerals, such as phyllosilicates, may prove especially challenging due to the complex interaction between the crystal structure and the laser pulse upon applying a high electric field. Micas are a representative group of nonswelling clay minerals of relevance to a number of scientific and technological fields. In this study, a Mg-rich biotite was analyzed by APT to generate preliminary data on nonisotropic minerals and to investigate the effect of the crystallographic orientation on mica chemical composition and structure estimation. The difference in results obtained for specimens extracted from the (001) and (hk0) mica surfaces indicate the importance of both experimental parameters and the crystallography. Anisotropy of mica has a strong influence on the physicochemical properties of the mineral during field evaporation and the interpretation of APT data. The promising results obtained in the present study open the way to future innovative APT applications on mica and clay minerals and contribute to the general discussion on the challenges for the analysis of geomaterials by atom probe tomography. 2026-02-18T13:13:19Z 2026-02-18T13:13:19Z 2022 journal article Cappelli, C.; Pérez Huerta, A.; Alam, S. B. y Prozorov, T. (2022). Atom probe tomography analysis of mica. Microscopy and Microanalysis (2022), 28, 1207–1220 doi:10.1017/S1431927621012940 1435-8115 1431-9276 https://hdl.handle.net/10481/111207 10.1017/S1431927621012940 eng http://creativecommons.org/licenses/by-nc-nd/4.0/ open access Attribution-NonCommercial-NoDerivatives 4.0 Internacional Cambridge University Press