The Graphitization of Diamond and the Nature of Cliftonite

H. J. Grenville-Wells
University College, London

Summary: Diamond heated in vacuo to about 2000° C. is wholly or partially converted to graphite which has a strong preferred orientation, the [0001] axis of the graphite being associated with the diamond [111] axis irrespective of the original habit of the diamond. The preferred orientation of the graphite in cliftonite, however, has been shown to involve the association of the [0001] axis with the cube axes of the crystal, thus casting doubt on the possibility that cliftonite is a pseudomorph after diamond. The graphite itself appears in both cases to be imperfectly crystallized, and is neither α- nor β-graphite, nor the usual mixture of the two. It has been shown by means of divergent-beam X-ray photographs that the Inosaicity of diamonds can be increased by heat-treatment.

Mineralogical Magazine; March 1952 v. 29; no. 216; p. 803-816; DOI: 10.1180/minmag.1952.029.216.01
© 1952, The Mineralogical Society
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