Use and Substitutes
Semola rimacinata is finely milled durum wheat semolina. Milling it at home is rarely worth it, but using it is straightforward.
For shaping pizza
Mix 2 tbsp semola with 2 tbsp regular wheat flour and dust the work surface thinly. This prevents sticking and burns less quickly than plain flour.
Substitute
For dusting, rice flour works 1:1 and releases especially well from the dough. Fine durum wheat semolina also works 1:1 but feels coarser. In the dough itself, replace semola with the same amount of type 550 wheat flour, and use 5-10 ml less water per 100 g at first, since regular flour often absorbs less water.
Not ideal
Cornmeal prevents sticking too, but leaves noticeably coarser, corn-like grains on the base.