Contributions to Gemology No.3 - The challenge of the identification of a new gemstone - New gem mineral Pezzottaite - Atomic arrangements
Adolf Peretti; Detlef Günther; Josef Mullis; Karl Ramseyer; Bernard Grobéty
Gemresearch Swisslab AG (2004)
In Collection
Gemology, Gemstones, Beryl, Pezzottaite, Madagascar
In 2002, a new gem mineral of commercial importance was discovered - pezzottaite of the beryl group. This volume is a case study of identifying and describing a new mineral. The identification of this particular mineral provided two major challenges: (1) the determination of the chemical composition, and (2) the identification of its crystallo structure (the geometrical arrangement of the atoms in three dimensions.
Pezzottaite contains several light elements - such as hydrogen, lithium, and beryllium, which cannot be directly analyzed by quantitative methods commonly used for mineral analysis such as electron microprobe (EMPA) or XRF analysis. Instead, measurement by Laser Ablation Mass Spectroscopy, as well as conventional methods used for chemical analysis.
Determination of the atomic structure required combination of various analytical techniques was necessary. It was discovered that the unit-cell of had unusually large dimensions, which is best described as a superstructure of beryl. Also, the number of atoms necessary to define the crystal structure turned out to be unusually high in comparison with other beryl- group mineral.
Based on the material's composition and structure, it was clear a new mineral had been found. It was named pezzottaite.
Product Details
Edition 2nd
Series Contributions to Gemology
Issue No. 3
No. of Pages 14
Height x Width 305 x 215  mm
Personal Details
Read It Yes
Store Mineralogical Society of America
Location A 3
Purchase Price 40.00 CHF
Purchase Date mars 2013
Condition First hand
Links GemResearch Swisslab
Mineralogical Society of America