I want to try making a mosaic pattern on a cake, and though I was initially planning to make the little tiles out of fondant, a friend suggested using gumpaste instead. I was if anyone with experience making a mosaic-style design on a cake had better luck using one material over the other?
depends. if you are going to be making tiles, and have them set before you put them on the cake, id go for gumpaste, or a mix of the two. if you are just making them and putting them straight on the cake, id use fondant. if you are careful it wont stretch.
although gumpaste is edible, its not as tasty as fondant! so if you can, youd be aswell using fondant if its over the whole cake, less waste.
Fondant would be much more eating friendly
The two mediums are so much alike there really isn't that much difference. Since you plan on making small tiles there should be no stretching problems. Do roll it on the thin side so they don't stick out from the cake or you may have to fill in between each tile.