Diamond formation in the Earth's mantle

Abstract

Introduction. Despite the wealth of new and exciting information gathered in the past few years, a clear physical model of diamond formation has yet to emerge. A clear recipe for producing synthetic diamonds may be obtained, in principle, from a production engineer in a diamond factory. My feeling is that we are not yet at a stage where we, as diamond geologists, can give a clear recipe for what should be done for growing natural diamonds in the Earth's mantle. What are the sources of carbon for diamonds? What is the main carbon-bearing species during migration from the source and accumulation at the site of diamond formation? What are the physical conditions? What is the chemical reaction for diamond formation and how long does