X-ray section topographs of a cube-shaped diamond.

Abstract

A suite of X-ray section topographs of a cube-shaped diamond were taken around a Bragg condition of 220 at every 0.05o rotation of the reflection angle, theta . A four-circle diffractometer constructed for synchrotron radiation use was employed to take these photographs. The topographic pictures indicate that the cube-shaped diamond consisted of two parts which were completely different in sub-microscopic texture. The inner part was composed of four growth sectors dividing the cube-shaped diamond almost along the diagonals, each of which was rotated by about 0.025o relative to its neighbour. The outer part was highly mosaic-like and consisted of an accumulation of very small sub-grains which were approx 800 A in diameter and oriented almost coaxially with the inner part but in the range of about 0.8o.-T.Y.