Geometric Art Deco Diamond Engagement Ring in Platinum.  This wonderful Art Deco engagement ring features a 1.05 carat Old European cut diamond set in platinum. The H color center stone is held by fishtail prongs and sits in a square shaped mounting with its single cut accent stones flanking it in trapezoid shaped sections. The accent stones also have open spaces surrounding three sides for a partially floating look. This is a very symmetrical engagement ring with lovely filigree work and engravings down the shoulders.