Hi, marti, I didn't research it online. My late husband is the one who found the epoxy product that I used instead of grout. It was a labor-intensive process, even for a small counter area.

Because of the method used to 'push' grout into the cracks between tiles, I don't know how one would keep the colors from mixing. I've read about grout colorants--for those who are unhappy with the color of their grout. Maybe you could use a small brush to 'paint' different colors. You might email BillVincent, a GW bathroom forum tiling expert, and ask him about it.

I've been out of town, but now back to working on guest room closets. :)

I've heard of removing old grout by chipping it out, then re-grouting. Sounds like an awful lot of work. I have purchased in a hardware store, not online, a product called "Grout Shield" which consists of two bottles- one liquid to clean the grout, another bottle is "color-sealer". The first bottle you apply with what looks like a metal toothbrush, you really scrub the grout, the second is applied with a paintbrush. Comes in various colors, white, cream, gray,etc, but I don't remember any multi-color.

I should have been more specific about the epoxy product (Milliput), and method I used, in case anyone else needs the info. On the marble tile kitchen counter (baking/buffet run), I did not use grout. I butted the tiles and filled in the groove with the epoxy putty, pushing it in, and scraping it off flush with the tile surface. Then I lightly sanded to smooth it to match the hand polished finish on the tile. The New St.Laurent marble tile has lots of lines, fissures, and fossils, so it was pretty easy to match the tiles, then use a pin to scratch the epoxy to 'connect' the lines. For wider veins, I scratched lines, then used my daughters' nail polish, sparingly, to match the color of the marble--mostly pearly white, but that variety has some orange-y veins, too. One advantage to using the epoxy, is that if it ever chips out, a small amount can be mixed to fill the chip. The product comes in three colors, black, white, and gray. The black matched my tile well, but I could have mixed different colors and pushed small bits into the grooves. As with any two-part epoxy, working time is limited before it hardens. It was an experiment, but almost two years later, it's held up very well.

I'd never use that method and product on a framed sub-floor. On a poured slab, it might work; however, it would still be a huge investment in expense, time, effort (on your knees, on cold, hard tile).

If you look closely, you can see the lines between the tiles in this in-progress pic of the kitchen counter: