Something about diamond testers

Robert James FGA, GG, President of the International School of Gemology, reported difficulty in synthetic moissanite identification because of an optical effect resembling chatoyancy.
The report informs that all traditional diamond testers showed this as a diamond. Due to the high concentration of inclusions, the usually diagnostic doubling of facet junctions seen in synthetic moissanite was virtually impossible to see without a microscope.
The mineral is identified by a microscope 90x study and with Raman Spectroscopy.
One of the conclusions of the author of this study is to not trust those diamond testers on the market that are supposed to separate diamonds from synthetic moissanite.

The report can be found here