Nice work. Looks like you had a lot of book matched tiles to work with. Personally I wind it worthwhile to epoxy two tiles together to create a more heavy duty shelf.

Bottom shelf was shock tested yesterday.

Take one skull, with some skill and knowledge but not a lot of common sense.

Add loss of location while grouting.

Quickly stand up=

One sore head, a slightly bruised ego, some mild self deprecations and a shelf still intact.

Will try the epoxy bond next time--I have seen tile done this way but never liked the exposed edges--would work nice with the stone.