Argentium® sterling silver, 14 karat palladium white gold
Before I proposed to my wife, she made it clear that she had no intention of wearing an engagement ring—which is of course a perplexing statement to make to a goldsmith. So I jokingly asked "what am I supposed to give you, an engagement pendant?" As funny as it was, it got me thinking about what I could give her that would be an appropriate gesture.
Naturally, I ran with the joke, but with an eye to the future. This washer-shaped pendant is made from a silver and white gold mokume-gane billet, which is a Japanese style of mixing metals by folding them together to get a woodgrain-like pattern—a process similar to the creation of Damascus steel. Here, the lighter sections are silver and the darker striations are an alloy of white gold and palladium.
Beyond the joke, though, was a purpose—the pendant actually became her wedding ring. There is a metalsmithing technique whereby a washer can be hammered around its own central hole resulting in a flat ring, which allows for a patterned ring with no seam anywhere along the shank. That flat ring can also then be domed from the inside to give it curvature along the cross section.
So while my wife might not have been willing to wear an engagement ring, she essentially wore her wedding ring next to her heart for ten months before the wedding. See the finished ring here!