I'm not familiar with Michael Anthony's connection with invisible
set stones (I would think it would have to be a patent, not a
copyright, because it has to do with the technique of setting, rather
than the appearance of the piece), but for more on
invisible cut diamonds, you might be interested in an article by
Arthur Skuratowicz in the October 2002 issue of AJM magazine in which
he describes the process of invisible setting, including the process
of cutting the grooves in the diamonds.
Alas, while Arthur describes how the grooves are cut, he doesn't
mention anyone who sells them pre-grooved. I hope someone else will
be able to direct you to a source of supply.
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