Plastic deformation in natural diamonds: Rose channels associated to mechanical twinning

Research areas:
Year:
2016
Keywords:
Plastic deformation, Natural diamond, Rose channels, Mechanical micro-twin, High pressure high temperature cracks
Authors:
  • M. Schoor
  • J. C. Boulliard
  • E. Gaillou
  • O. Hardouin Duparc
  • I. Estève
  • B. Baptiste
  • Benjamin Rondeau
  • E. Fritsch
Journal:
Diamond and Related Materials
Volume:
66
Pages:
102 - 106
ISSN:
0925-9635
BibTex:
Abstract:
Hollow channels in diamond are well acknowledged to be the result of dissolution processes. In this article we
demonstrate that some hollowchannels in natural diamonds are the consequence of intense plastic deformation
by mechanical twinning. Two mixed-habit diamonds presenting numerous geometrical hollowtubeswere studied.
X-ray Laue analyses showed the presence of microtwins. At the intersection of microtwins, displacements
and cracks are generated, creating the hollow channels observed. The presence of the cracks seems to have
released the internal stress, as there was less to no signs of deformation at and around them. Further dissolutions
are sometimes but not always seen within the cavities. Mechanical twinning, so far mostly identified in pink to
purple diamonds, might be more widespread than originally thought in natural diamonds.