Irregular slabs, also known as mosaic, opus incertum, Palladian, terrazzo, are
porphyry slabs of irregular shape with varying thickness and size.
Uses of porphyry slabs
Opus incertum is one of the oldest ways to use porphyry, together with setts. The main applications of porphyry are in outdoor paving (sidewalks, pavements, squares, courtyards, paths for homes and gardens) and for outdoor facing (walls, terraces, roofs).
The upper face of the porphyry slabs (i.e. the one used for walking), is quarry face, so relatively even and flat, thanks to the characteristics of porphyry which is quarried in the heart of the porphyritic platform of the Adige valley, in Albiano, Trentino.
| Irregular slabs, thin |
1 to 3 |
60 to 70 |
| Irregular slabs, normal |
2 to 5 |
80 to 90 |
| Irregular slabs, giant, thin type |
2 to 4 |
70 to 80 |
| Irregular slabs, giant |
3 to 7 |
100 to 110 |