Published online by Cambridge University Press: 28 February 2011
Electron energy loss spectroscopy of voidite defects in natural diamond shows that they are composed of nitrogen which is likely to be present in the form of solid N2 under high pressure (ca. 10 GPa). A similar examination of platelets has failed to reveal any nitrogen in them. It is proposed that the voidites are generated by a discontinuous precipitation mechanism as the platelets decompose. A similar study of the the chemistry of nanometre sized mineral particles present in most diamonds shows they are related to the earth's magma although there are notable differences.