I think painting the base a color that matches one in the mosaic tiles would be nice. A lot easier and less time consuming as well. It's looking good so far- hope you post a final work pic.

Thanks! That's where I'm leaning. I've got my eye on Lastiseal color sealer. It's reasonably priced, seals and colors in one step and has the look of an acid stain. I'm wondering if anyone has experience with it? (And yes! When it's done I'd love to post a picture if you're interested in checking it out. That's half the fun, IMO, LOL)

Loribee2.....Your bench is so beautiful. Personally, I would let the beautiful natural cement show on the base. It won't compete with the seat after you have put the mosaic tiles on it. I feel that if you painted it, it might take away from the seat. Maybe you could use a gray for your grout?

You've got a point. I wonder if a simple glossy sealer would give it some interest while maintaining the natural look. The color sealer I'm thinking about is supposed to be transparent (unless you put on more coats). I kind of like the mottled effect of the stone itself. You've definitely got me thinking about just starting with the top, going with a gray grout then seeing what I've got before committing to more. And I appreciate the confirmation from both of you that mosaic on the base would most likely be too much (and more time and weight!).

Thanks much for the opinions! It helps to see what others think.