Green Sapphire Diamond Engagement Ring in 14k White Gold.  Using a sapphire for an engagement ring is a durable and practical way to go a different route than a diamond. This ring features an amazing green emerald cut sapphire that is set in 14 karat white gold with diamond accents. The 2.03 carat emerald has a wonderful bluish green color and is encrusted with .62 carats of round brilliant cut diamonds to complete the look.