A thorough characterisation of porphyry from China (Province of Fujian) was made, regarding three chromatic variants: red, brown and grey. The properties object of study are: petrographic, chemical and mineralogical analysis, real and apparent density as well as open and total porosity, water absorption at atmospheric pressure, resistance to salt crystallization, rupture energy, compressive strength, flexural strength, abrasion resistance and slip resistance. The achieved results remain into the expected ones for this kind of stone. Nevertheless, small differences were found according to the colour of the sample. Finally, those properties which are covered in the CE marking were compared with the representative values of commercial samples from countries as Italy, Argentina and Mexico.
The technology development has enabled the production of new type of materials and handling techniques of natural stone. Historically, natural stone has been used for making tools and other equipment, as well as ornamental carving in buildings and monuments, some of them quite relevant as (EXAMPLES). At present, main use of natural stone remains as construction material, because of its resistance and durability [1].
Porphyry is a clear example of this; because of the natural beauty and its good physical-mechanical properties, it has been used from the most ancient civilisations (Assyrian, Babylonian, Egyptian and Roman) to present [2,3]. For instance, the oldest known example of porphyry is a bust dating back to the Egypt dynasty XXVI (664-525 a. C.) [4].
The earliest known porphyry quarries are found in the mountains of the Red Sea, Egypt, known as Mons Porphyrites [5]. The most intensive extraction took place under the Roman Empire, between the first and the end of the fifth century [6], even though other authors suggest that the quarries could have been abandoned in the middle of the fourth century [4,7].
The word "porphyry" comes from the Greek "πορwύρα porphúra" which means purple, considered to be the colour of royalty in the past [8]. It is precisely its unique colour the reason for its high price, being a symbol of prestige and imperial status. Hence, it was known as "Imperial Porphyry" in the past, being its use exclusively reserved for the imperial court [9].