A PERIPATETIC APPROACH TO DIAMONDISM UTILIZING CARBON IN A SOLID SOLUTION OF A METAL OF GROUP VIII AS A SOURCE

Some theories pertaining to the mantle contain strong structural views. One such is that diamond is formed in stable old cratons (SOC). SOC alone is not able to account for an expansive and compelling finds of diamond in recent years. A peripatized contemplation is attempted utilizing carbon in a solid solution of a metal of Group VIII as a source. Part of the compositional basis from which my argument is derived are iron-bearing inclusions in diamonds (single crystal and polycrystalline) from the Democratic Republic of the Congo and carbonado from Central African Republic.

Exsolution lamellae of graphite in iron were utilized to calculate stoichiometries of bulk composition of relevent phases and assemblages relative to the Fe-C eutectic, to examine chemical reactions, thermal history, and diffusion coefficients. The presence of a carbide, Fe3C, (Orthorhombic a=4.525, b=5.091 c=6.744 Å) is due to chemical reaction post completion of the growth of diamond, rather than contamination, as evidenced by well defined boundary of cavities aligned with iron.

My approach has potential application to some of the issues regarding the presence of silicon carbide. Some studies have proclaimed an origin of great depth any time a grain of SiC is found; whereas others cautioned of possibility of abbrasive preparation. The uncertainty is due to difficulty in documentijng proof that an inclusion is an inclusion, i.e. without any microstructures connecting it to a grain boundary. Most literature relied on the authors' impression. My approach provides a third, less inflammatory interpretation which deemphasizes the uncertainty by examining independently the thermal history. Sector-zoned diamonds richly embedded with inclusions provide for the reconstruction of generations of heat transfer.

It is an indisputable reality that a significant number of diamond deposits are located in the proximity of a metal deposit. Calculation is made to illustrate that in a hypothetically seismically-induced impact wherein a sufficiently large boulder presses a sufficiently small-unit of carbon in metal is capable of generating pressure exceeding 30 kb. Combined with a hypothetical simultaneous thunder-induced heat transfer, transformation of carbon to diamond in a small scale is possible. Prediction is made, based upon known Group VIII metal deposits, of possible future finds of diamond.