question about changing colour background for stained glass

Hi everyone,

I got a little iron table from a junk fair. It is covered in dark blue ceramic tiles. I am thinking of making a mosaic on top of it. I also have a stained glass sun cut that would be lovely in the center. The problem is that the dark blue tiles show through the glass sun. How should i cover the place where the stained glass will be? what kind of paint should I use? The part with the mosaic will be OK as the tiles have solid colours. I just need an idea for where the stained glass sun will be glued to the center of the top.

Thank you.:o)