Vaterite Crystals Contain Two Interspersed Crystal Structures

See allHide authors and affiliations

Science  26 Apr 2013:
Vol. 340, Issue 6131, pp. 454-457
DOI: 10.1126/science.1232139

You are currently viewing the abstract.

View Full Text

Log in to view the full text

Log in through your institution

Log in through your institution

Double Vision

Vaterite is the least stable form of anhydrous crystalline calcium carbonate. While rarely found in geological contexts, it is an important biological precursor and occurs as a minor component in the shells of some organisms. The crystal structure of vaterite has long been debated with no model able to explain all the experimentally observed diffraction spots. Kabalah-Amitai et al. (p. 454) show that vaterite contains two coexisting crystallographic structures that form a pseudo-single crystal.


Calcite, aragonite, and vaterite are the three anhydrous polymorphs of calcium carbonate, in order of decreasing thermodynamic stability. Although vaterite is not commonly found in geological settings, it is an important precursor in several carbonate-forming systems and can be found in biological settings. Because of difficulties in obtaining large, pure, single crystals, the crystal structure of vaterite has been elusive for almost a century. Using aberration-corrected high-resolution transmission electron microscopy, we found that vaterite is actually composed of at least two different crystallographic structures that coexist within a pseudo–single crystal. The major structure exhibits hexagonal symmetry; the minor structure, existing as nanodomains within the major matrix, is still unknown.

View Full Text

Stay Connected to Science