Retro Round Diamond Engagement Ring in 14K Yellow Gold.  This Retro engagement ring features a .15 carat round brilliant cut diamond set in 14 karat white gold with the band finished in 14 karat yellow gold. The two-toned design looks amazing with the strength of the fishtail prongs that extend down the basket. The small accent diamonds on the shoulders add a bit more to the bright sparkle of this darling engagement ring.