Grout and Mortar

Here you can get unsanded grout in 8 colors and a nice white tile mortar which is appropriate for items you're making for outdoor use as well as art projects. The grout is sold in 1/2 pound units.

White Grout
One nice thing about cement based grout is that is cleans up fairly easily throughout the entire project. You can get quite a few different colors of grout at The Home Depot in both sanded and unsanded mixtures.
Charcoal Grout
Once again, cement based grout is a good choice for projects both indoor and outdoor. Sanded grout is better for outdoor projects and is necessary if your grout lines are wider than 1/8".
Cement based tile mortar which is specifically formulated for use with glass tile and porcelain. This mortar is good for use when you are making things which will be left outside.