They are certainly lovely, but what specifically and technically do they achieve over standard facets?
Ann, Due to the curved nature of the cut surface, the gem material
acts as a lens, focusing the incoming light. This style is also
called OMF - Optically Magnified Faceting. The curved facets are
VERY bright.
Frank Romano
“Gemcutters are Multifaceted Individuals”
http://www.romanogems.com