Iron Island B3F.
Roselia
You can find a Shiny Stone in Route 228 in Pokemon Diamond and Pearl. In Pokemon Platinum, you can also find a Shiny Stone on Iron Island.
In the underground.
End of Iron Island
if you dig underground you'll eventually find thunder stone then after a while you'll find shiny stone ;^)
the Pokemon that shiny stone evolves is Togetic -> Togekiss Roselia -> Roserade
togetic into togekiss and rosiela into roserade
in Pokemon diamond and pearl, its in iron island
In Pokemon Diamond and Pearl, the Shiny Stone can be found in Route 228 and on Iron Island. In the Pokemon Platinum, it can be found in these locations and in Route 210 as well.
you can dig 1 out of the walls underground
The Shiny Stone does not exist in Pokemon Gold, Silver and Crystal it was added when Diamond and Pearl came out and if you're referring to Pokemon HeartGold, the Shiny Stone can be found at the National Park and can be won if you come in 1st place in the Bug Catching Contest.
in order to evolve Roselia you have to use a sun stone on it You use a shiny stone, not a sun stone.