Vintage new without tags 18kt Yellow GE "RSC" marquise-shaped Glam "Cubic Zirconia" dome cluster ring, size 6, band is 2mm wide

Best guess for the stones is CZ or Swarovski crystals, since RSC (RS Covenant jewelry maker) uses both for their rings 

Fabulous glitz "glam" Hollywood cluster ring 

Hallmarked: 18Kt GE RSC - 6grams