.22ct diamond halo 18kw gold pendant mounting

A beautiful 18 karat white gold diamond halo mounting is ready to set a 6 mm or 3/4 carat round center stone. The pendant sparkles with 18 round brilliant cut G-VS quality diamonds, including three set in the bale for a total weight of .22 carats.  What will it be...A classic diamond or a colored gemstone for the center?  The choice is yours!  Center stone and chain sold separately.