Tried glue and it didn't work.
What type of glue have you already tried?
E6000 works great or even better get some mortar (for placing bricks & stones) at DIY store
Bondo. It is a thick, two-part polyester resin used to repair everything from automobile bodies to home foundations. Will easily do the trick. Good Luck!
Get some Kwik-Fix project glue.. Two parts a glue and spray. It glues just about anything together in a few seconds and bonds tightly. I've fixed ceramics, plastic, glass... it is amazing.
You will need to use something to hold it firmly in place while it dries like wire, cord, duct tape, or all of them/