Os polimorfos de carbonato de cálcio: uma síntese fácil de aragonita The polymorphs of calcium carbonate: an easy synthesis of aragonite

• Published in: Química nova Vol. 31; no. 1; pp. 178 - 180
• Main Authors: Karl E. Bessler, Laécio C. Rodrigues
• Format: Journal Article
• Language: English
• Published: Sociedade Brasileira de Química 01-01-2008
• Subjects: aragonite; polymorphism; synthesis
• ISSN: 0100-4042; 1678-7064
• DOI: 10.1590/S0100-40422008000100032

Aragonite is a metastable polymorph of calcium carbonate. The calcareous exoskeletons of some organisms like corals or molluscs consist essentially of aragonite. The questions of how, and why these organisms prefer the thermodynamically unstable aragonite for the construction of their hard shells are discussed. The importance of the biomineralization process for the development of new materials is outlined. In the experimental part, a very simple synthesis of polycrystalline aragonite is performed, using carbonated mineral water available at the market. The synthesized aragonite is easily identified by its infrared spectrum.