Me and Ruth (my Wife) have just spent an enjoyable hour creating the rock-face texture for Quarry Transfer. We used ‘Unibond: Tile on Floor’ grout, which we bought from B&Q a year or two ago.
The great thing about using tile grout (instead of polyfiller) is that the stuff usually comes in a variety of colours (in this case a dark grey), so if you pick the right shade, any worn or chipped corners will not be an eye sore.
The other benefit of using grout is that the odds of the chipping ever happening are extremely low. Once dry, Quarry Transfer will likely survive a trip out the window and remain unscathed.
We had an assortment of tools to use, but in the end it was much easier to apply the grout with gloved hands.
The front of the diorama was not worked on because I want to have a bit more of a think about that area.