NOOOOOOOOOO!!! Don’t glue it back together into a cracked vase! That’s too difficult to do…and would look kinda strange in my opinion. Take the vase and smash it into smaller pieces with a hammer. Buy yourself a cheap glass vase and glue the pieces. Or get a small table and glue the tiles on top as a design.
Like these examples below:
http://www.artbytracieritz.com/sitebuildercontent/sitebuilderpictures/kl_mosaic_vase.jpg
http://www.jessicacraven.com/images/blue_swirl_vase.jpg
http://www.metalwerxmosaics.com/Pics/Tables/Mosaic%20Table%203.jpg