Vanadium carbides in shungite are shown to be present in several forms, which reflects the distinctive conditions of their formation. An ordered carbon film revealed on the vanadium carbide particles could protect the particles from transformations for a long time. The parageneses of vanadium carbide and roscoelite occur, indicating that roscoelite in shungite rocks may be a secondary mineral formed upon vanadium carbide decomposition.

Electron backscatter diffraction (EBSD) is a powerful tool to visualize and differentiate between foraminiferal test structures, by providing information on crystal orientation and crystal sizes. This can be used to trace diagenetic recrystallization, altering geochemical proxy signals. The sediment samples from a core from the equatorial Pacific used here, spanning the last 45 Myr, showed no evidence for foraminiferal recrystallization, highlighting the suitability as geochemical proxy archive.