Nano and Micro Diamond Formation in Nature: Ultrafine Carbon Particles on Earth and Space (SpringerBriefs in Earth Sciences)

Carbon is a many-sided chemical element, as it forms millions of compounds related to both biochemical and geochemical processes. Moreover, elemental carbon occurs in various polymorphs (or allotropes), such as graphite, diamond, amorphous carbon, lonsdaleite, and fullerenes. The physical properties of the different carbon poly-morphs vary widely due to the different ways in which the atoms in each are bonded. Diamond is the most compact, Sp3-bonded, polymorph of carbon, having nearly twice the density of graphite. The study of diamond has seen a recent burst of activity in geochemistry and astrophysics, in novel methods of synthesis, and in the develop-ment of useful applications. Diamond is recognized as an extraordinary recorder of astrophysical and geodynamic events that extend from the most remote regions of space to Earth’s deep interior. As will be specified later, different types of diamonds have been recognized based on their size, geological occurrence, morphological char-acteristics, types of solid or fluid inclusions, etc. The processes of formation of some diamond types still raise many contentious questions. The formation of macroscopic diamonds is mainly connected with deep-seated igneous rocks, such as kimberlites and lamproites, and therein mantle xenoliths. To date, in mineralogy, there is no widely accepted definition of a size boundary between kimberlitic microdiamond and macrodiamond. Contents Abbreviations Physical Symbols 1 Introduction References 2 Diamond Thermodynamic Stability: The Paradox of Crystal Size References 3 Experimental Data on Nanocarbon Formation Under Low P‒T Conditions References 4 Diamond Formation in the Oceanic Lithosphere 4.1 Nano- and Micron-Sized Diamond Formation in the Oceanic Lithosphere 4.1.1 Nanodiamond and Organic Compound Formation in Oceanic Serpentinite Systems 4.1.2 General Notes on the Serpentinization of the Oceanic Lithosphere 4.1.3 Nanodiamonds in Serpentinites—A Case Study from Sicily and Other Occurrences 4.1.4 Nanodiamonds in Serpentinites as Proxies for the Emergence of Life on Early Earth 4.1.5 Micron-Sized Diamonds in Ophiolites—Insights into Their Formation 4.1.6 Nano- and Micron-Sized Diamond Formation in Hawaiian Salt Lake Crater Xenoliths 4.1.7 Conclusions 4.2 Carbonado Genesis References 5 Nanocarbon and Microdiamond Formation in the Lithogenesis and Metamorphic Processes 5.1 Nanocarbon Formation in the Lithogenesis and Contact Metamorphism Processes 5.1.1 Nanodiamond Formation in the Lithogenesis and Contact Metamorphism Processes 5.1.2 Fullerene and Fullerene-Like Phase Formation During Metamorphic Processes 5.1.3 Conclusions 5.2 Micron-Sized Diamond Formation During Metamorphic Processes 5.2.1 Worldwide Metamorphic Diamonds 5.2.2 Kokchetav Diamond Deposit 5.2.3 Kokchetav Diamond-Bearing Crustal Rocks—An Overview 5.2.4 Mineralogical Features of Kokchetav Metamorphic Diamonds 5.2.5 Processes of Kokchetav Microdiamond Formation 5.2.6 Conclusions References 6 Diamonds in Kimberlites and Their Xenoliths: A Reappraisal 6.1 Introduction 6.2 Diamond Inclusions 6.3 Diamond Formation from Fluids in the Upper Mantle 6.4 Diamond Formation in the Postmagmatic Processes of Kimberlites 6.5 The Genesis of the Extralarge Type IIa Diamonds 6.6 Conclusions References 7 Conclusions References In this book, readers will gain a deep understanding of the distinct characteristics and intricate formation mechanisms behind each type of diamond. A standout feature of this book is its in-depth exploration of nanodiamonds, shedding light on their unique formation processes. The narrative is thoughtfully organized, covering four main categories of natural diamonds and their related formation processes: 1)Interstellar nanodiamond particles; 2) Nano- and microcrustal diamonds associated with coals, sediments, and metamorphic rocks; 3) Nanodiamonds and microdiamonds associated with secondary alterations of mafic and ultramafic rocks mainly in the oceanic lithosphere; 4) Mantle-derived diamonds associated with kimberlites and their xenoliths, such as peridotites and eclogites. With clarity and precision, this book caters to both researchers and students in the fields of mineralogy and mineral formation. This book serves as an invaluable resource, offering an all-encompassing perspective on diamond formation, appealing to those curious minds eager to delve into the captivating realm of these precious gems.