(via ICA Early Warning Flash, No.65, December 21, 1992) GAGTL writes:
A pink cut-cornered square modified brilliant diamond was submitted to the Gem Testing Laboratory for the determination of the origin of its color—whether it was of natural or treated color and for the determination of the color grade.
The diamond weighed 3.35 carats and measured approx. 8.32x8.08x6.53mm. Upon examination with a 10x lens, one was struck by the many feathers visible within the stone. Viewing the diamond from various angles and by transmitted light, one could detect many surface reaching fractures displaying iridescent colors implying these were filled with air. But also noticeable were the tell-tale blue and orange flashes in some fractures indicating that these had been filled with an artificial material.
Spectroscopic investigation of the stone proved it to be a diamond of natural color and of type IaAB. The nature of the internal colored grain lines and the frosted appearance of some of the fractures indicated that the diamond may have been mined in Argyle, Australia.
If graded, the color grade would be fancy pink and the clarity grade would be pique III. However, The Gem Testing Laboratory does not issue grading reports on fracture filled diamonds. The poor clarity grade apparent subsequent to fracture treatment and the presence of untreated air-filled fractures indicate that the clarity enhancement process was not successful.
Although the Laboratory has tested fracture-filled diamonds before, this is the first instance we have seen of a fancy colored diamond being so treated.
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