Finally found a very hi res photo of the famous earring. It is flat and enamel filled. But yes, it is silver attached to a gold loop.Question on this "Then" earring. It looks to me like he placed a silver crossbones on his gold loop. I have placed my quick mockup example next to it for color reference:
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Finding the exact earring is not likely so besides sculpting one, this purchased charm is a close second at 3/4 inch tall at ten feet away. List any sources you might have for crossbone charms and opinions on this color combo.