Porphyry calibrated thickness 1.3 cm / 2.00 cm to be laid with glue flamed surface finish.
Porphyry is a volcanic rock; it is formed by glassy paste in which small crystals of quartz are absorbed , so that the rock is also named “quartz porphyry”.
The colour of porphyry varies from light gray to a medium brown.
This sort of stone is often used for external pavings because it is very resistant to cold and hot temperatures. We can mainly see it , in various floorings ( as “ bolognini or San Peter’s cobblestones in medium size plates ) as well as used for coatings.