My original engagement ring was a beautiful heart-shaped pink tourmaline with small diamonds set into the yellow gold band. We had a wedding band custom made to match it and the set was lovely and dainty and very appropriate for the young bride that I was at the time. Coloured stoned weren't common then - I got SO many compliments on that ring!
Like others have mentioned about their jemstones though, the tourmaline was soft and the points on the cut wore badly over time. Then a few years ago I had a mishap and it was distroyed. I replaced it with several "temporary" rings but have not ever again found one I love. I've actually just ordered a custom anniversary band (round pink sapphires and diamonds) that I hope will become my "forever" ring. I'm looking forward to its arrival in time for our 22nd anniversary on Saturday.