The Round Brilliant is by no means the only round design for faceted stones, 
some others are:
Swiss cut
Split brilliant cut
English round cut brilliant
Twentieth-century cut
King cut
Magna cut

The more common commercial  shapes:
Oval cut
Marquise or Navette cut
Emerald Cut
Pear shaped cut
Heart shaped cut
Square emerald cut
Single cut
This is a useful, quick and easy cut to use with Accent stones
These are interesting for a number of reasons, rough is cheap, cutting is only 4 settings,
And as a learning funtion they are the essence of the optical factors, of 
reflection and refraction. And you could make wages by processing them from rough to 
finished gem. Used in a finished design, you have a 10 keystone profit margin.

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