I tried it once. I don't know if it was the particular paint I chose or the amount I used, but it gave off a terrible smell and the project ended up being very weak.
I wouldn't hurt to try...unless that bad smell is toxic :)

I was wondering about using the colorant that is added to white base paint to make specific colors. It is quite intense. I was thinking of using it as part of the liquid in making the concrete, still keeping the 10% rule in mind.

Sue

Sue, where do you find that stuff and what is it called? I'd like to take a look at that, as well.

Just as a side note for people making indoor projects; water colors give a great look, too. The advantage to water colors over acrylic is that you can add multiple penetrating layers, whereas acrylic paint layers will start to seal it and only build up on top of the previous layers. I tried this on a section of my fountain and really thought it looked better. I then sealed it with an acrylic matte finish to prevent it from washing out.

Belgianpup--That is what I used for my blue bowl. A real intense dark blue tint for paint. Mixed it with white portland and white silica sand. Turned out baby blue and the first plants I potted in it died. Not sure if it was the coloring or bad plants. I think the color. It did give it a more uniform look I thought.
Paws