Solitaire European Cut Diamond Engagement Ring PlatinumSolitaire European Cut Diamond Engagement Ring Platinum. This fancy solitaire engagement ring features a . 95 carat Old European cut diamond with an interestingly angled diamond halo and all set in platinum. The clever diamond halo angles outward from the girdle and below that the shoulders feature neat little rings and the rest of the shank is a clean high polish. This is a fantastic engagement ring with slight twist on a classic look.