Retro Solitaire European Cut Diamond Engagement Ring.  This Retro engagement rings beauty is in its simplicity.  A single solitary diamond is set on a yellow gold band.  The center diamond is set low in white gold in what is known as a fishtail basket.  This allows light to penetrate from every angle, maximizing the brilliance of the stone.  This two tone ring from the 1940s is a quite versatile if your looking to accent with diamond wedding bands.