Electron Backscatter Diffraction (EBSD)
[001] Inverse pole figure map (color) overlain on an image quality map (grayscale) of a calcite grain from a carbonaceous chondrite meteorite.
Orientation map of a brachiopod (T. retusa). Brachiopods are marine invertebrates that have an extensive fossil record. They are a much used source of information on the composition and temperature of ancient oceans. The sample is entirely composed of calcite. The colors indicate slight differences in orientation.
Courtesy of Martin Lee, Paul Dalbeck and Maggie Cusack, Division of Earth Sciences, University of Glasgow
Three calcium carbonate polymorphs in Unio Pictorum (Painter's Mussel) shell
- Map collected with a Hikari Super EBSD Analysis System with TEAM™ EBSD software
- Shown: Phase and IPF maps on Image Quality (left) and PRIAS™ center map showing orientation contrast (top)
- CaCO3 typically occurs in two polymorphs: calcite and aragonite
- Occasionally a 3rd polymorph can be observed, vaterite, which may for example form as initial mineral deposit in shells to repair damage
- Vaterite is a metastable phase, which is highly susceptible to beam damage and requires a gentle electron beam for successful analysis