A new allotropic form of carbon from the ries crater

Science. 1968 Jul 26;161(3839):363-4. doi: 10.1126/science.161.3839.363.

Abstract

A new allotropic form of carbon occurs in shock-fused graphite gneisses in the Ries Crater, Bavaria. The assemblage in which it occurs consists of hexagonal graphite, rutile, pseudobrookite, magnetite, nickeliferous pyrrhotite, and baddeleyite. Electron-probe analyses indicate that the new phase is pure carbon. It is opaque and much more strongly reflecting than hexagonal graphite. Measurement of x-ray diffraction powder patterns leads to cell dimensions a = 8.948 +/- 0.009, c = 14.078 +/- 0.017 angstroms, with a primitive hexagonal lattice.