Dive into Forever with an Aquamarine Engagement Ring. This lovely “sea water” gemstone, closely related to emerald, symbolizes honesty, faithfulness, and love, the essential ingredients for a successful relationship and a great choice for an engagement ring. Aquamarines vary in color, ranging from deep blue to bluish-green, and intensity increases with the stone size. They are durable, affordable, and just what you need for a statement engagement ring.