When it comes to colouring your own grout, the possibilities are endless and the same steps apply, no matter the hue or grout type. This is an easy way to add even more personality to your mosaic pieces than just using ready-made grout colours.
Choose a colour you love from among the acrylic paint color choices available at any craft or discount shop. Always buy at least two bottles of the colour. Some regularly available brands are Apple Barrel Colors, Delta Ceramcoat and Folk Art. They are very inexpensive and come in small 60 ml (2 ounce) bottles.
Buy the grout you will use in Pure White not Snow White. Snow white grout may appear grayish or off-white, which will be a little yellowish. To get the truest, clearest colour, you need to start with real white.
Stop mixing the grout just before it reaches peanut butter consistency. Then, when the grout is still a little crumbly, add your paint. It will probably take the entire bottle of paint to achieve the hue you want because the white of the grout will dilute the colour. Squirt some colour in, mix it up and evaluate.
Squirt some more colour in and re-mix well if the grout color is too light. If the grout is too wet, add some grout powder, a little at a time, to thicken it up. If the grout is too dry but just the right colour, simply add a tiny bit of water at a time until it reaches that perfect-to-use peanut butter consistency.
Experiment and adjust the powder, water and paint until the grout and colour is just right to begin grouting your mosaic project. Next time, you can experiment further with metallic paints and paints with sparkles for a fanciful effect, as well as darker versus lighter colours.
When choosing a colour, buy the darkest version of the colour you want for the end result because the white of the grout dilutes the colour when you mix. For example, a dark burgundy paint will turn light pink when mixed with white grout, and hunter green will turn into mint or sage. If you want dark, saturated grout colours, you can purchase ready-made ones like navy blue, brown, black and terra-cotta. You can never really create dark grout colours yourself because you are always adding white. Black grout (while the messiest) will give your project the gorgeous effect of "stained glass," especially if your tiles are bright colors. Plain white grout always looks fresh and summery no matter what the tile choice. Remember some basic grout colour choice rules when matching a colour to your project. Outdoor projects require darker grouts, like black and terra-cotta, which do not show mildew or dirt. Indoor projects can take any colour at all. Choose a color that contrasts with your tile colour scheme to really show it off. Always keep lots of library books about mosaic projects on hand to get visual inspiration and ideas about different grout colour choices.