If you do a search, you will see posts on the subject of gold and platinum....some claim the two metals will wear each other down (down know which wears which) more than when two rings of the same metal are worn together.....
I know you are probably asking about wearing the two COLOR metals together, but there also is the other issue...................
If your question is about wearing the two colors together, I have a good friend who wears her white gold e-ring with narrow yellow gold wedding bands on each side and it looks incredible!
Yes, that is my question. I have reset my e-ring from 14kt yellow gold to platinum plain solitaire setting, and I still wanted to wear it with my original plain wedding that is in 14kt yellow gold. But if this looks odd, then I would consider buying a plain platinum wedding band.
I have heard of people doing that with certain rings as well. My mom has a ring from Tiffanys which has diamonds and is in yellow gold and she wears that with a platium band it looks very nice, the white seems to bring out the white in diamonds.
It sounded werid to me at first but it actually looks very nice.
Good luck