“Oslo” 3-stone ring in palladium featuring 1.90 ct. Rose Spinel accented by 1.85 ct. pair of Blue Spinel; size 7 but can size to fit you. How to Wear: These hues of rose and blue are surprisingly neutral and go with a lot of wardrobing options. This ring was designed for wear alone or stacked with other rings, even a wedding band. Spinel, with good durability and a hardness of 8, is strong enough for an engagement ring.