Then apply a tile and grout sealer to seal the grout.
Tiling a pizza oven dome.
A brick pizza oven dome is usually constructed as either an igloo or barrel dome out of medium density fire bricks both shapes are constructed in much the same fashion with bricks mortar and usually with a supporting frame.
The dome itself a series of self supporting circular brick chains that curve inward until they meet at the keystone at the oven top.
Reading through your replies to various comments it looks like glass or porcelain tiles are best to use and to use a thinset mortar to bond and grout the tiles.
To get a perfect shape dome put the sand in the shape of a dome.
Then using a string and marking pen build a compass half the diameter of your oven 18 or 21 and mark the circumference of your oven floor.
It is to do with the sand and afterward place the bricks onto them.
Tiles of different designs can be interchanged on same oven.
You can also frame and decorate the front portion of the dome arch with granite or other materials.
I love in the north east of england in the uk we have an outdoor pizza oven which i am looking to mosaic tile.