Here are some rings I made up for my brother-in-law and my sister-in-law who both got married this summer (Not to each other to clarify. What would just be wrong. :s)
The rings were made in Zbrush then 3D printed and cast by the good folks at Kraftwurx.com
The lady's band in 18k palladium white gold with 18k yellow gold insert and a .6 Carat green diamond.
The man's band is 14k palladium white gold band with 14k yellow gold sing wave insert.