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 (Q)I 
            have been using powder grout when mosaicing with ceramic tiles. I 
            found that after a few days, a few small hairline cracks appear. Can 
            anyone offer a solution?
 (A) 
              This has happened to me when I have worked on table tops and then 
              either the base reacts or I move it before it is set (I'm not sure 
              which causes it). What I have done is to mix some very thing grout 
              and pour into the cracks. It worked fine for my small projects so 
              fa (Q)I've 
            just completed a mosaic and I find that the grout I have used is too 
            light in colour. As a result it has spoilt the effect of the design. 
            Does anyone have advice on how I can darken the grout please?
 (A) 
              I've used regular acrylic paint to highlight grout (gold paint on 
              black grout, rubbed off), and assume you could do the same to darken 
              the grout. Also, have read in several books that others have used 
              acrylic paint to completely color white grout. I'd do a test first. 
              Sheri Hooton (A) 
              According to the book, Mosaics with Natural Stone, by Walter Lauppi, 
              Pg. 34. COLORED MORTAR Any mortar can be colored by adding pigment 
              dissolved in water or by using colored cement in the mixture. Use 
              only earth colors, such as terre verte (earth green), raw or burnt 
              sienna, raw or burnt umber, English or Indian red, vine black, etc. 
              Chemical pigments are decomposed by cement. The color pigment or 
              colored-cement is best mixed with water and added as a liquid to 
              the finished mortar. An important point to remember in adding pigment 
              is that the color will appear 50 per cent brighter when dry. (Author 
              uses term mortar for grout.) The point the author is trying to make 
              is that pretty much any color pigment will work. Chemical pigments, 
              such as in liquid paints, will decompose and leach away over time, 
              due to a chemical reaction caused by the cement. Sorry this doesn't 
              solve your current dilemma, but it's good information to know. MM:(useful 
              info from Cat in SC (Q)Is 
            there a supplier of colored grout in the United States?
 
 (A) 
              I have used this grout for an out door wall mural in zone 4. comes 
              in lots of color sanded or unsanded, latex-fortified. made by DAP 
              the product is called: durabond ceramic tile grout. might check 
              your local hardware store. they can order it for you or check for 
              tile suppliers in your area. ask for a color chart. Pamela, Oswayo, 
              Pa. (Q)I'm 
            a mosaic artist who has been doing mosaics for many years, and I have 
            a problem that has come up repeatedly. To one degree or another, I 
            have problems with dark grouts. Recently I tried a new product from 
            Tile Lab, that is supposed to be an excellent sealer for outdoor works. 
            However, when the mosaics got rained on the other day, and I saw what 
            happened to the color of the grout, I was very upset because the black 
            grout which was mixed with latex instead of water, prior to using 
            the sealer a week or so later, turned absolutely grayish-white on 
            the surface! I've talked to the company and other industry professionals 
            and no one can tell me a thing! These pieces are done on cement. Outdoor 
            use, and I have no idea what is the cause, or if there is an easy 
            surface remedy to return the surface to black? Public show coming 
            up, as well as city looking at work for future project, this can't 
            be happening!! Anyone know what's going on? Please reply in a hurry!
 (A) 
              I have also had this problem and it was finally discovered, after 
              a lot of attempts, that the dark grouts were being coated with a 
              whitish coating by the nature of the hard water chemicals in our 
              water source. We had only recently moved into our studio... This 
              coating never appeared in our light grouts for obvious reasons. 
              Adjusting the water was the solution...I have never had a problem 
              since!! I do not know the quality of your water source but this 
              was our experience with that whitish coating. I never successfully 
              fixed the grout of the affected mosaics. It was an expensive live-and-learn 
              experience!!! MaryAnn Jagg |  |