Also known as the ‘trilogy’ style, three-stone engagement rings are an incredibly romantic choice. That’s because the three stones are symbolic. They are traditionally said to represent past, present, and future, or you, me and us. Trilogy rings are very versatile, depending on the size, type, and shape of the stones used. One popular option is to have a large center diamond with two smaller flanking stones or three mid-size stones of equal size. A modern take on the trilogy style is to use a color gem as the center stone and accent it with diamonds. Whatever you decide, this design is as meaningful as it is beautiful.