[Spanko]

The simplest way is just placing it somewhere and then checking in the board array at that tiles position.
Another way is just by checking up on the numbers at the bottom of the tileset screen, one of them is the x,y position of the tile on the tileset, take it's x and y and do the following calculation: x+y*16 and you have the tiles index.
It's probably not as efficient as making Graal make use of the tiles hex value, but it does work.