Chromium: Its Physicochemical Behavior and Petrologic Significance

Chromium: Its Physicochemical Behavior and Petrologic Significance is a collection of papers presented at an interdisciplinary conference on the physicochemical behavior and petrologic significance of chromium, held at the Geophysical Laboratory of the Carnegie Institution of Washington on January 7-8, 1974. Contributors explore the physicochemical behavior and petrologic significance of chromium and cover a wide range of topics, including the mineralogy of chromium and thermochemistry of chromium compounds.

Comprised of 23 chapters, this book begins with a discussion on phase relations in chromium oxide-containing systems at elevated temperatures, followed by an analysis of the chromium-oxygen system at high oxygen pressures. Subsequent chapters focus on crystal field effects in chromium and its partitioning in the mantle; trivalent and divalent chromium ions in spinels; distribution and significance of chromium in meteorites; and chrome-spinel in progressive metamorphism. The paragenesis of zoned chromite from central Manitoba is also considered, along with postcumulus and subsolidus equilibration of chromite and coexisting silicates in the Eastern Bush veld Complex. The final chapter presents a hypothesis of origin for podiform chromite deposits.

This monograph will be of interest to physicists, chemists, and geologists.

Contenu

Foreword
Phase Relations in Chromium Oxide-Containing Systems at Elevated Temperatures
The System Chromium-Oxygen at High Oxygen Pressures
Thermochemistry of Chromium Compounds, Especially Oxides at High Temperature
Solid Oxide Electrolyte Emf Cell Determination of the Standard Free Energy of Cr2O3 and Applications to Chromiumbearing
Mineral Systems
Preparation of Cr2O3 Crucibles and the Defect Structure of Cr2O3
Smelting Chrome Ore
Crystal Field Effects in Chromium and its Partitioning in the Mantle
Crystal-Field Effects in Spinel: Oxidation States of Iron and Chromium
Trivalent and Divalent Chromium Ions in Spinels
Magnetic Properties of Chromium Chalcogenide Spinels
Magnetochemical Characterization of Fe(FexCr2-x)O4 Spinels
Mineralogy of Chromium
Distribution and Significance of Chromium in Meteorites
Chromium and the Genesis of Diamond
Chromite Spinels from Ultramafic Xenoliths
Coexisting Spinel and Silicates in Alpine Peridotites of the Granulite Facies
Chrome-Spinel in Progressive Metamorphism-a Preliminary Analysis
The Paragenesis of Zoned Chromite from Central Manitoba
Crystallization Sequences in the Muskox Intrusion and Other Layered Intrusions-II. Origin of Chromitite Layers and Similar Deposits of Other Magmatic Ores
Postcumulus and Subsolidus Equilibration of Chromite and Coexisting Silicates in the Eastern Bushveld Complex
Reaction Trends Shown by Chrome-Spinels of the Rhum Layered Intrusion
A comparison of Chrome-Spinels in Ophiolites and Mantle Diapirs of Newfoundland
A Hypothesis of Origin for Podiform Chromite Deposits