This is a beautiful stack from Cass Partington called MOANA, it has 3 rings.
1) 18ct white gold band (2.6mm x 1.9mm) with 1 black diamond (2.3mm), and 3 green sapphires (2.3mm)
2) 18ct white gold band (2mm x 1.9mm)
3) 18ct white gold band (2.6mm x 1.9mm) with 3 white diamonds (2.3mm) 1 green sapphire (2.3mm) and 1 black diamond (2.3mm)
Size O
Sapphires, black diamonds, white diamonds, 18ct white gold